Updating go depencancies. Switching to go1.6 vendoring (#2949)

56 files changed, 13816 insertions, 0 deletions

diff --git a/vendor/gopkg.in/asn1-ber.v1/.travis.yml b/vendor/gopkg.in/asn1-ber.v1/.travis.yml
new file mode 100644
index 000000000..44aa48b87
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/.travis.yml
@@ -0,0 +1,15 @@
+language: go
+go:
+    - 1.2
+    - 1.3
+    - 1.4
+    - 1.5
+    - tip
+go_import_path: gopkg.in/asn-ber.v1
+install:
+    - go list -f '{{range .Imports}}{{.}} {{end}}' ./... | xargs go get -v
+    - go list -f '{{range .TestImports}}{{.}} {{end}}' ./... | xargs go get -v
+    - go get code.google.com/p/go.tools/cmd/cover || go get golang.org/x/tools/cmd/cover
+    - go build -v ./...
+script:
+    - go test -v -cover ./...
diff --git a/vendor/gopkg.in/asn1-ber.v1/LICENSE b/vendor/gopkg.in/asn1-ber.v1/LICENSE
new file mode 100644
index 000000000..744875676
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2012 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/gopkg.in/asn1-ber.v1/README.md b/vendor/gopkg.in/asn1-ber.v1/README.md
new file mode 100644
index 000000000..e3a9560d6
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/README.md
@@ -0,0 +1,24 @@
+[![GoDoc](https://godoc.org/gopkg.in/asn1-ber.v1?status.svg)](https://godoc.org/gopkg.in/asn1-ber.v1) [![Build Status](https://travis-ci.org/go-asn1-ber/asn1-ber.svg)](https://travis-ci.org/go-asn1-ber/asn1-ber)
+
+
+ASN1 BER Encoding / Decoding Library for the GO programming language.
+---------------------------------------------------------------------
+
+Required libraries: 
+   None
+
+Working:
+   Very basic encoding / decoding needed for LDAP protocol
+
+Tests Implemented:
+   A few
+
+TODO:
+   Fix all encoding / decoding to conform to ASN1 BER spec
+   Implement Tests / Benchmarks
+
+---
+
+The Go gopher was designed by Renee French. (http://reneefrench.blogspot.com/)
+The design is licensed under the Creative Commons 3.0 Attributions license.
+Read this article for more details: http://blog.golang.org/gopher
diff --git a/vendor/gopkg.in/asn1-ber.v1/ber.go b/vendor/gopkg.in/asn1-ber.v1/ber.go
new file mode 100644
index 000000000..25cc921be
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/ber.go
@@ -0,0 +1,504 @@
+package ber
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"reflect"
+)
+
+type Packet struct {
+	Identifier
+	Value       interface{}
+	ByteValue   []byte
+	Data        *bytes.Buffer
+	Children    []*Packet
+	Description string
+}
+
+type Identifier struct {
+	ClassType Class
+	TagType   Type
+	Tag       Tag
+}
+
+type Tag uint64
+
+const (
+	TagEOC              Tag = 0x00
+	TagBoolean          Tag = 0x01
+	TagInteger          Tag = 0x02
+	TagBitString        Tag = 0x03
+	TagOctetString      Tag = 0x04
+	TagNULL             Tag = 0x05
+	TagObjectIdentifier Tag = 0x06
+	TagObjectDescriptor Tag = 0x07
+	TagExternal         Tag = 0x08
+	TagRealFloat        Tag = 0x09
+	TagEnumerated       Tag = 0x0a
+	TagEmbeddedPDV      Tag = 0x0b
+	TagUTF8String       Tag = 0x0c
+	TagRelativeOID      Tag = 0x0d
+	TagSequence         Tag = 0x10
+	TagSet              Tag = 0x11
+	TagNumericString    Tag = 0x12
+	TagPrintableString  Tag = 0x13
+	TagT61String        Tag = 0x14
+	TagVideotexString   Tag = 0x15
+	TagIA5String        Tag = 0x16
+	TagUTCTime          Tag = 0x17
+	TagGeneralizedTime  Tag = 0x18
+	TagGraphicString    Tag = 0x19
+	TagVisibleString    Tag = 0x1a
+	TagGeneralString    Tag = 0x1b
+	TagUniversalString  Tag = 0x1c
+	TagCharacterString  Tag = 0x1d
+	TagBMPString        Tag = 0x1e
+	TagBitmask          Tag = 0x1f // xxx11111b
+
+	// HighTag indicates the start of a high-tag byte sequence
+	HighTag Tag = 0x1f // xxx11111b
+	// HighTagContinueBitmask indicates the high-tag byte sequence should continue
+	HighTagContinueBitmask Tag = 0x80 // 10000000b
+	// HighTagValueBitmask obtains the tag value from a high-tag byte sequence byte
+	HighTagValueBitmask Tag = 0x7f // 01111111b
+)
+
+const (
+	// LengthLongFormBitmask is the mask to apply to the length byte to see if a long-form byte sequence is used
+	LengthLongFormBitmask = 0x80
+	// LengthValueBitmask is the mask to apply to the length byte to get the number of bytes in the long-form byte sequence
+	LengthValueBitmask = 0x7f
+
+	// LengthIndefinite is returned from readLength to indicate an indefinite length
+	LengthIndefinite = -1
+)
+
+var tagMap = map[Tag]string{
+	TagEOC:              "EOC (End-of-Content)",
+	TagBoolean:          "Boolean",
+	TagInteger:          "Integer",
+	TagBitString:        "Bit String",
+	TagOctetString:      "Octet String",
+	TagNULL:             "NULL",
+	TagObjectIdentifier: "Object Identifier",
+	TagObjectDescriptor: "Object Descriptor",
+	TagExternal:         "External",
+	TagRealFloat:        "Real (float)",
+	TagEnumerated:       "Enumerated",
+	TagEmbeddedPDV:      "Embedded PDV",
+	TagUTF8String:       "UTF8 String",
+	TagRelativeOID:      "Relative-OID",
+	TagSequence:         "Sequence and Sequence of",
+	TagSet:              "Set and Set OF",
+	TagNumericString:    "Numeric String",
+	TagPrintableString:  "Printable String",
+	TagT61String:        "T61 String",
+	TagVideotexString:   "Videotex String",
+	TagIA5String:        "IA5 String",
+	TagUTCTime:          "UTC Time",
+	TagGeneralizedTime:  "Generalized Time",
+	TagGraphicString:    "Graphic String",
+	TagVisibleString:    "Visible String",
+	TagGeneralString:    "General String",
+	TagUniversalString:  "Universal String",
+	TagCharacterString:  "Character String",
+	TagBMPString:        "BMP String",
+}
+
+type Class uint8
+
+const (
+	ClassUniversal   Class = 0   // 00xxxxxxb
+	ClassApplication Class = 64  // 01xxxxxxb
+	ClassContext     Class = 128 // 10xxxxxxb
+	ClassPrivate     Class = 192 // 11xxxxxxb
+	ClassBitmask     Class = 192 // 11xxxxxxb
+)
+
+var ClassMap = map[Class]string{
+	ClassUniversal:   "Universal",
+	ClassApplication: "Application",
+	ClassContext:     "Context",
+	ClassPrivate:     "Private",
+}
+
+type Type uint8
+
+const (
+	TypePrimitive   Type = 0  // xx0xxxxxb
+	TypeConstructed Type = 32 // xx1xxxxxb
+	TypeBitmask     Type = 32 // xx1xxxxxb
+)
+
+var TypeMap = map[Type]string{
+	TypePrimitive:   "Primitive",
+	TypeConstructed: "Constructed",
+}
+
+var Debug bool = false
+
+func PrintBytes(out io.Writer, buf []byte, indent string) {
+	data_lines := make([]string, (len(buf)/30)+1)
+	num_lines := make([]string, (len(buf)/30)+1)
+
+	for i, b := range buf {
+		data_lines[i/30] += fmt.Sprintf("%02x ", b)
+		num_lines[i/30] += fmt.Sprintf("%02d ", (i+1)%100)
+	}
+
+	for i := 0; i < len(data_lines); i++ {
+		out.Write([]byte(indent + data_lines[i] + "\n"))
+		out.Write([]byte(indent + num_lines[i] + "\n\n"))
+	}
+}
+
+func PrintPacket(p *Packet) {
+	printPacket(os.Stdout, p, 0, false)
+}
+
+func printPacket(out io.Writer, p *Packet, indent int, printBytes bool) {
+	indent_str := ""
+
+	for len(indent_str) != indent {
+		indent_str += " "
+	}
+
+	class_str := ClassMap[p.ClassType]
+
+	tagtype_str := TypeMap[p.TagType]
+
+	tag_str := fmt.Sprintf("0x%02X", p.Tag)
+
+	if p.ClassType == ClassUniversal {
+		tag_str = tagMap[p.Tag]
+	}
+
+	value := fmt.Sprint(p.Value)
+	description := ""
+
+	if p.Description != "" {
+		description = p.Description + ": "
+	}
+
+	fmt.Fprintf(out, "%s%s(%s, %s, %s) Len=%d %q\n", indent_str, description, class_str, tagtype_str, tag_str, p.Data.Len(), value)
+
+	if printBytes {
+		PrintBytes(out, p.Bytes(), indent_str)
+	}
+
+	for _, child := range p.Children {
+		printPacket(out, child, indent+1, printBytes)
+	}
+}
+
+// ReadPacket reads a single Packet from the reader
+func ReadPacket(reader io.Reader) (*Packet, error) {
+	p, _, err := readPacket(reader)
+	if err != nil {
+		return nil, err
+	}
+	return p, nil
+}
+
+func DecodeString(data []byte) string {
+	return string(data)
+}
+
+func parseInt64(bytes []byte) (ret int64, err error) {
+	if len(bytes) > 8 {
+		// We'll overflow an int64 in this case.
+		err = fmt.Errorf("integer too large")
+		return
+	}
+	for bytesRead := 0; bytesRead < len(bytes); bytesRead++ {
+		ret <<= 8
+		ret |= int64(bytes[bytesRead])
+	}
+
+	// Shift up and down in order to sign extend the result.
+	ret <<= 64 - uint8(len(bytes))*8
+	ret >>= 64 - uint8(len(bytes))*8
+	return
+}
+
+func encodeInteger(i int64) []byte {
+	n := int64Length(i)
+	out := make([]byte, n)
+
+	var j int
+	for ; n > 0; n-- {
+		out[j] = (byte(i >> uint((n-1)*8)))
+		j++
+	}
+
+	return out
+}
+
+func int64Length(i int64) (numBytes int) {
+	numBytes = 1
+
+	for i > 127 {
+		numBytes++
+		i >>= 8
+	}
+
+	for i < -128 {
+		numBytes++
+		i >>= 8
+	}
+
+	return
+}
+
+// DecodePacket decodes the given bytes into a single Packet
+// If a decode error is encountered, nil is returned.
+func DecodePacket(data []byte) *Packet {
+	p, _, _ := readPacket(bytes.NewBuffer(data))
+
+	return p
+}
+
+// DecodePacketErr decodes the given bytes into a single Packet
+// If a decode error is encountered, nil is returned
+func DecodePacketErr(data []byte) (*Packet, error) {
+	p, _, err := readPacket(bytes.NewBuffer(data))
+	if err != nil {
+		return nil, err
+	}
+	return p, nil
+}
+
+// readPacket reads a single Packet from the reader, returning the number of bytes read
+func readPacket(reader io.Reader) (*Packet, int, error) {
+	identifier, length, read, err := readHeader(reader)
+	if err != nil {
+		return nil, read, err
+	}
+
+	p := &Packet{
+		Identifier: identifier,
+	}
+
+	p.Data = new(bytes.Buffer)
+	p.Children = make([]*Packet, 0, 2)
+	p.Value = nil
+
+	if p.TagType == TypeConstructed {
+		// TODO: if universal, ensure tag type is allowed to be constructed
+
+		// Track how much content we've read
+		contentRead := 0
+		for {
+			if length != LengthIndefinite {
+				// End if we've read what we've been told to
+				if contentRead == length {
+					break
+				}
+				// Detect if a packet boundary didn't fall on the expected length
+				if contentRead > length {
+					return nil, read, fmt.Errorf("expected to read %d bytes, read %d", length, contentRead)
+				}
+			}
+
+			// Read the next packet
+			child, r, err := readPacket(reader)
+			if err != nil {
+				return nil, read, err
+			}
+			contentRead += r
+			read += r
+
+			// Test is this is the EOC marker for our packet
+			if isEOCPacket(child) {
+				if length == LengthIndefinite {
+					break
+				}
+				return nil, read, errors.New("eoc child not allowed with definite length")
+			}
+
+			// Append and continue
+			p.AppendChild(child)
+		}
+		return p, read, nil
+	}
+
+	if length == LengthIndefinite {
+		return nil, read, errors.New("indefinite length used with primitive type")
+	}
+
+	// Read definite-length content
+	content := make([]byte, length, length)
+	if length > 0 {
+		_, err := io.ReadFull(reader, content)
+		if err != nil {
+			if err == io.EOF {
+				return nil, read, io.ErrUnexpectedEOF
+			}
+			return nil, read, err
+		}
+		read += length
+	}
+
+	if p.ClassType == ClassUniversal {
+		p.Data.Write(content)
+		p.ByteValue = content
+
+		switch p.Tag {
+		case TagEOC:
+		case TagBoolean:
+			val, _ := parseInt64(content)
+
+			p.Value = val != 0
+		case TagInteger:
+			p.Value, _ = parseInt64(content)
+		case TagBitString:
+		case TagOctetString:
+			// the actual string encoding is not known here
+			// (e.g. for LDAP content is already an UTF8-encoded
+			// string). Return the data without further processing
+			p.Value = DecodeString(content)
+		case TagNULL:
+		case TagObjectIdentifier:
+		case TagObjectDescriptor:
+		case TagExternal:
+		case TagRealFloat:
+		case TagEnumerated:
+			p.Value, _ = parseInt64(content)
+		case TagEmbeddedPDV:
+		case TagUTF8String:
+			p.Value = DecodeString(content)
+		case TagRelativeOID:
+		case TagSequence:
+		case TagSet:
+		case TagNumericString:
+		case TagPrintableString:
+			p.Value = DecodeString(content)
+		case TagT61String:
+		case TagVideotexString:
+		case TagIA5String:
+		case TagUTCTime:
+		case TagGeneralizedTime:
+		case TagGraphicString:
+		case TagVisibleString:
+		case TagGeneralString:
+		case TagUniversalString:
+		case TagCharacterString:
+		case TagBMPString:
+		}
+	} else {
+		p.Data.Write(content)
+	}
+
+	return p, read, nil
+}
+
+func (p *Packet) Bytes() []byte {
+	var out bytes.Buffer
+
+	out.Write(encodeIdentifier(p.Identifier))
+	out.Write(encodeLength(p.Data.Len()))
+	out.Write(p.Data.Bytes())
+
+	return out.Bytes()
+}
+
+func (p *Packet) AppendChild(child *Packet) {
+	p.Data.Write(child.Bytes())
+	p.Children = append(p.Children, child)
+}
+
+func Encode(ClassType Class, TagType Type, Tag Tag, Value interface{}, Description string) *Packet {
+	p := new(Packet)
+
+	p.ClassType = ClassType
+	p.TagType = TagType
+	p.Tag = Tag
+	p.Data = new(bytes.Buffer)
+
+	p.Children = make([]*Packet, 0, 2)
+
+	p.Value = Value
+	p.Description = Description
+
+	if Value != nil {
+		v := reflect.ValueOf(Value)
+
+		if ClassType == ClassUniversal {
+			switch Tag {
+			case TagOctetString:
+				sv, ok := v.Interface().(string)
+
+				if ok {
+					p.Data.Write([]byte(sv))
+				}
+			}
+		}
+	}
+
+	return p
+}
+
+func NewSequence(Description string) *Packet {
+	return Encode(ClassUniversal, TypeConstructed, TagSequence, nil, Description)
+}
+
+func NewBoolean(ClassType Class, TagType Type, Tag Tag, Value bool, Description string) *Packet {
+	intValue := int64(0)
+
+	if Value {
+		intValue = 1
+	}
+
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	p.Data.Write(encodeInteger(intValue))
+
+	return p
+}
+
+func NewInteger(ClassType Class, TagType Type, Tag Tag, Value interface{}, Description string) *Packet {
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	switch v := Value.(type) {
+	case int:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint:
+		p.Data.Write(encodeInteger(int64(v)))
+	case int64:
+		p.Data.Write(encodeInteger(v))
+	case uint64:
+		// TODO : check range or add encodeUInt...
+		p.Data.Write(encodeInteger(int64(v)))
+	case int32:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint32:
+		p.Data.Write(encodeInteger(int64(v)))
+	case int16:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint16:
+		p.Data.Write(encodeInteger(int64(v)))
+	case int8:
+		p.Data.Write(encodeInteger(int64(v)))
+	case uint8:
+		p.Data.Write(encodeInteger(int64(v)))
+	default:
+		// TODO : add support for big.Int ?
+		panic(fmt.Sprintf("Invalid type %T, expected {u|}int{64|32|16|8}", v))
+	}
+
+	return p
+}
+
+func NewString(ClassType Class, TagType Type, Tag Tag, Value, Description string) *Packet {
+	p := Encode(ClassType, TagType, Tag, nil, Description)
+
+	p.Value = Value
+	p.Data.Write([]byte(Value))
+
+	return p
+}
diff --git a/vendor/gopkg.in/asn1-ber.v1/content_int.go b/vendor/gopkg.in/asn1-ber.v1/content_int.go
new file mode 100644
index 000000000..1858b74b6
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/content_int.go
@@ -0,0 +1,25 @@
+package ber
+
+func encodeUnsignedInteger(i uint64) []byte {
+	n := uint64Length(i)
+	out := make([]byte, n)
+
+	var j int
+	for ; n > 0; n-- {
+		out[j] = (byte(i >> uint((n-1)*8)))
+		j++
+	}
+
+	return out
+}
+
+func uint64Length(i uint64) (numBytes int) {
+	numBytes = 1
+
+	for i > 255 {
+		numBytes++
+		i >>= 8
+	}
+
+	return
+}
diff --git a/vendor/gopkg.in/asn1-ber.v1/header.go b/vendor/gopkg.in/asn1-ber.v1/header.go
new file mode 100644
index 000000000..123744e9b
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/header.go
@@ -0,0 +1,29 @@
+package ber
+
+import (
+	"errors"
+	"io"
+)
+
+func readHeader(reader io.Reader) (identifier Identifier, length int, read int, err error) {
+	if i, c, err := readIdentifier(reader); err != nil {
+		return Identifier{}, 0, read, err
+	} else {
+		identifier = i
+		read += c
+	}
+
+	if l, c, err := readLength(reader); err != nil {
+		return Identifier{}, 0, read, err
+	} else {
+		length = l
+		read += c
+	}
+
+	// Validate length type with identifier (x.600, 8.1.3.2.a)
+	if length == LengthIndefinite && identifier.TagType == TypePrimitive {
+		return Identifier{}, 0, read, errors.New("indefinite length used with primitive type")
+	}
+
+	return identifier, length, read, nil
+}
diff --git a/vendor/gopkg.in/asn1-ber.v1/identifier.go b/vendor/gopkg.in/asn1-ber.v1/identifier.go
new file mode 100644
index 000000000..f7672a844
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/identifier.go
@@ -0,0 +1,103 @@
+package ber
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"math"
+)
+
+func readIdentifier(reader io.Reader) (Identifier, int, error) {
+	identifier := Identifier{}
+	read := 0
+
+	// identifier byte
+	b, err := readByte(reader)
+	if err != nil {
+		if Debug {
+			fmt.Printf("error reading identifier byte: %v\n", err)
+		}
+		return Identifier{}, read, err
+	}
+	read++
+
+	identifier.ClassType = Class(b) & ClassBitmask
+	identifier.TagType = Type(b) & TypeBitmask
+
+	if tag := Tag(b) & TagBitmask; tag != HighTag {
+		// short-form tag
+		identifier.Tag = tag
+		return identifier, read, nil
+	}
+
+	// high-tag-number tag
+	tagBytes := 0
+	for {
+		b, err := readByte(reader)
+		if err != nil {
+			if Debug {
+				fmt.Printf("error reading high-tag-number tag byte %d: %v\n", tagBytes, err)
+			}
+			return Identifier{}, read, err
+		}
+		tagBytes++
+		read++
+
+		// Lowest 7 bits get appended to the tag value (x.690, 8.1.2.4.2.b)
+		identifier.Tag <<= 7
+		identifier.Tag |= Tag(b) & HighTagValueBitmask
+
+		// First byte may not be all zeros (x.690, 8.1.2.4.2.c)
+		if tagBytes == 1 && identifier.Tag == 0 {
+			return Identifier{}, read, errors.New("invalid first high-tag-number tag byte")
+		}
+		// Overflow of int64
+		// TODO: support big int tags?
+		if tagBytes > 9 {
+			return Identifier{}, read, errors.New("high-tag-number tag overflow")
+		}
+
+		// Top bit of 0 means this is the last byte in the high-tag-number tag (x.690, 8.1.2.4.2.a)
+		if Tag(b)&HighTagContinueBitmask == 0 {
+			break
+		}
+	}
+
+	return identifier, read, nil
+}
+
+func encodeIdentifier(identifier Identifier) []byte {
+	b := []byte{0x0}
+	b[0] |= byte(identifier.ClassType)
+	b[0] |= byte(identifier.TagType)
+
+	if identifier.Tag < HighTag {
+		// Short-form
+		b[0] |= byte(identifier.Tag)
+	} else {
+		// high-tag-number
+		b[0] |= byte(HighTag)
+
+		tag := identifier.Tag
+
+		highBit := uint(63)
+		for {
+			if tag&(1<<highBit) != 0 {
+				break
+			}
+			highBit--
+		}
+
+		tagBytes := int(math.Ceil(float64(highBit) / 7.0))
+		for i := tagBytes - 1; i >= 0; i-- {
+			offset := uint(i) * 7
+			mask := Tag(0x7f) << offset
+			tagByte := (tag & mask) >> offset
+			if i != 0 {
+				tagByte |= 0x80
+			}
+			b = append(b, byte(tagByte))
+		}
+	}
+	return b
+}
diff --git a/vendor/gopkg.in/asn1-ber.v1/length.go b/vendor/gopkg.in/asn1-ber.v1/length.go
new file mode 100644
index 000000000..8e2ae4ddd
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/length.go
@@ -0,0 +1,71 @@
+package ber
+
+import (
+	"errors"
+	"fmt"
+	"io"
+)
+
+func readLength(reader io.Reader) (length int, read int, err error) {
+	// length byte
+	b, err := readByte(reader)
+	if err != nil {
+		if Debug {
+			fmt.Printf("error reading length byte: %v\n", err)
+		}
+		return 0, 0, err
+	}
+	read++
+
+	switch {
+	case b == 0xFF:
+		// Invalid 0xFF (x.600, 8.1.3.5.c)
+		return 0, read, errors.New("invalid length byte 0xff")
+
+	case b == LengthLongFormBitmask:
+		// Indefinite form, we have to decode packets until we encounter an EOC packet (x.600, 8.1.3.6)
+		length = LengthIndefinite
+
+	case b&LengthLongFormBitmask == 0:
+		// Short definite form, extract the length from the bottom 7 bits (x.600, 8.1.3.4)
+		length = int(b) & LengthValueBitmask
+
+	case b&LengthLongFormBitmask != 0:
+		// Long definite form, extract the number of length bytes to follow from the bottom 7 bits (x.600, 8.1.3.5.b)
+		lengthBytes := int(b) & LengthValueBitmask
+		// Protect against overflow
+		// TODO: support big int length?
+		if lengthBytes > 8 {
+			return 0, read, errors.New("long-form length overflow")
+		}
+		for i := 0; i < lengthBytes; i++ {
+			b, err = readByte(reader)
+			if err != nil {
+				if Debug {
+					fmt.Printf("error reading long-form length byte %d: %v\n", i, err)
+				}
+				return 0, read, err
+			}
+			read++
+
+			// x.600, 8.1.3.5
+			length <<= 8
+			length |= int(b)
+		}
+
+	default:
+		return 0, read, errors.New("invalid length byte")
+	}
+
+	return length, read, nil
+}
+
+func encodeLength(length int) []byte {
+	length_bytes := encodeUnsignedInteger(uint64(length))
+	if length > 127 || len(length_bytes) > 1 {
+		longFormBytes := []byte{(LengthLongFormBitmask | byte(len(length_bytes)))}
+		longFormBytes = append(longFormBytes, length_bytes...)
+		length_bytes = longFormBytes
+	}
+	return length_bytes
+}
diff --git a/vendor/gopkg.in/asn1-ber.v1/util.go b/vendor/gopkg.in/asn1-ber.v1/util.go
new file mode 100644
index 000000000..3e56b66c8
--- /dev/null
+++ b/vendor/gopkg.in/asn1-ber.v1/util.go
@@ -0,0 +1,24 @@
+package ber
+
+import "io"
+
+func readByte(reader io.Reader) (byte, error) {
+	bytes := make([]byte, 1, 1)
+	_, err := io.ReadFull(reader, bytes)
+	if err != nil {
+		if err == io.EOF {
+			return 0, io.ErrUnexpectedEOF
+		}
+		return 0, err
+	}
+	return bytes[0], nil
+}
+
+func isEOCPacket(p *Packet) bool {
+	return p != nil &&
+		p.Tag == TagEOC &&
+		p.ClassType == ClassUniversal &&
+		p.TagType == TypePrimitive &&
+		len(p.ByteValue) == 0 &&
+		len(p.Children) == 0
+}
diff --git a/vendor/gopkg.in/fsnotify.v1/.gitignore b/vendor/gopkg.in/fsnotify.v1/.gitignore
new file mode 100644
index 000000000..4cd0cbaf4
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/.gitignore
@@ -0,0 +1,6 @@
+# Setup a Global .gitignore for OS and editor generated files:
+# https://help.github.com/articles/ignoring-files
+# git config --global core.excludesfile ~/.gitignore_global
+
+.vagrant
+*.sublime-project
diff --git a/vendor/gopkg.in/fsnotify.v1/.travis.yml b/vendor/gopkg.in/fsnotify.v1/.travis.yml
new file mode 100644
index 000000000..00fd5dd30
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/.travis.yml
@@ -0,0 +1,29 @@
+sudo: false
+language: go
+
+go:
+  - 1.5.4
+  - 1.6.1
+  - tip
+
+matrix:
+  allow_failures:
+    - go: tip
+
+before_script:
+  - go get -u github.com/golang/lint/golint
+
+script:
+  - go test -v --race ./...
+
+after_script:
+  - test -z "$(gofmt -s -l -w . | tee /dev/stderr)"
+  - test -z "$(golint ./...     | tee /dev/stderr)"
+  - go vet ./...
+
+os:
+  - linux
+  - osx
+
+notifications:
+  email: false
diff --git a/vendor/gopkg.in/fsnotify.v1/AUTHORS b/vendor/gopkg.in/fsnotify.v1/AUTHORS
new file mode 100644
index 000000000..6438bb31c
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/AUTHORS
@@ -0,0 +1,43 @@
+# Names should be added to this file as
+#	Name or Organization <email address>
+# The email address is not required for organizations.
+
+# You can update this list using the following command:
+#
+#   $ git shortlog -se | awk '{print $2 " " $3 " " $4}'
+
+# Please keep the list sorted.
+
+Adrien Bustany <adrien@bustany.org>
+Amit Krishnan <amit.krishnan@oracle.com>
+Bjørn Erik Pedersen <bjorn.erik.pedersen@gmail.com>
+Caleb Spare <cespare@gmail.com>
+Case Nelson <case@teammating.com>
+Chris Howey <chris@howey.me> <howeyc@gmail.com>
+Christoffer Buchholz <christoffer.buchholz@gmail.com>
+Daniel Wagner-Hall <dawagner@gmail.com>
+Dave Cheney <dave@cheney.net>
+Evan Phoenix <evan@fallingsnow.net>
+Francisco Souza <f@souza.cc>
+Hari haran <hariharan.uno@gmail.com>
+John C Barstow
+Kelvin Fo <vmirage@gmail.com>
+Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp>
+Matt Layher <mdlayher@gmail.com>
+Nathan Youngman <git@nathany.com>
+Paul Hammond <paul@paulhammond.org>
+Pawel Knap <pawelknap88@gmail.com>
+Pieter Droogendijk <pieter@binky.org.uk>
+Pursuit92 <JoshChase@techpursuit.net>
+Riku Voipio <riku.voipio@linaro.org>
+Rob Figueiredo <robfig@gmail.com>
+Soge Zhang <zhssoge@gmail.com>
+Tiffany Jernigan <tiffany.jernigan@intel.com>
+Tilak Sharma <tilaks@google.com>
+Travis Cline <travis.cline@gmail.com>
+Tudor Golubenco <tudor.g@gmail.com>
+Yukang <moorekang@gmail.com>
+bronze1man <bronze1man@gmail.com>
+debrando <denis.brandolini@gmail.com>
+henrikedwards <henrik.edwards@gmail.com>
+铁哥 <guotie.9@gmail.com>
diff --git a/vendor/gopkg.in/fsnotify.v1/CHANGELOG.md b/vendor/gopkg.in/fsnotify.v1/CHANGELOG.md
new file mode 100644
index 000000000..675fab9eb
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/CHANGELOG.md
@@ -0,0 +1,291 @@
+# Changelog
+
+## v1.3.0 / 2016-04-19
+
+* Support linux/arm64 by [patching](https://go-review.googlesource.com/#/c/21971/) x/sys/unix and switching to to it from syscall (thanks @suihkulokki) [#135](https://github.com/fsnotify/fsnotify/pull/135)
+
+## v1.2.10 / 2016-03-02
+
+* Fix golint errors in windows.go [#121](https://github.com/fsnotify/fsnotify/pull/121) (thanks @tiffanyfj)
+
+## v1.2.9 / 2016-01-13
+
+kqueue: Fix logic for CREATE after REMOVE [#111](https://github.com/fsnotify/fsnotify/pull/111) (thanks @bep)
+
+## v1.2.8 / 2015-12-17
+
+* kqueue: fix race condition in Close [#105](https://github.com/fsnotify/fsnotify/pull/105) (thanks @djui for reporting the issue and @ppknap for writing a failing test)
+* inotify: fix race in test
+* enable race detection for continuous integration (Linux, Mac, Windows)
+
+## v1.2.5 / 2015-10-17
+
+* inotify: use epoll_create1 for arm64 support (requires Linux 2.6.27 or later) [#100](https://github.com/fsnotify/fsnotify/pull/100) (thanks @suihkulokki)
+* inotify: fix path leaks [#73](https://github.com/fsnotify/fsnotify/pull/73) (thanks @chamaken)
+* kqueue: watch for rename events on subdirectories [#83](https://github.com/fsnotify/fsnotify/pull/83) (thanks @guotie)
+* kqueue: avoid infinite loops from symlinks cycles [#101](https://github.com/fsnotify/fsnotify/pull/101) (thanks @illicitonion)
+
+## v1.2.1 / 2015-10-14
+
+* kqueue: don't watch named pipes [#98](https://github.com/fsnotify/fsnotify/pull/98) (thanks @evanphx)
+
+## v1.2.0 / 2015-02-08
+
+* inotify: use epoll to wake up readEvents [#66](https://github.com/fsnotify/fsnotify/pull/66) (thanks @PieterD)
+* inotify: closing watcher should now always shut down goroutine [#63](https://github.com/fsnotify/fsnotify/pull/63) (thanks @PieterD)
+* kqueue: close kqueue after removing watches, fixes [#59](https://github.com/fsnotify/fsnotify/issues/59)
+
+## v1.1.1 / 2015-02-05
+
+* inotify: Retry read on EINTR [#61](https://github.com/fsnotify/fsnotify/issues/61) (thanks @PieterD)
+
+## v1.1.0 / 2014-12-12
+
+* kqueue: rework internals [#43](https://github.com/fsnotify/fsnotify/pull/43)
+    * add low-level functions
+    * only need to store flags on directories
+    * less mutexes [#13](https://github.com/fsnotify/fsnotify/issues/13)
+    * done can be an unbuffered channel
+    * remove calls to os.NewSyscallError
+* More efficient string concatenation for Event.String() [#52](https://github.com/fsnotify/fsnotify/pull/52) (thanks @mdlayher)
+* kqueue: fix regression in  rework causing subdirectories to be watched [#48](https://github.com/fsnotify/fsnotify/issues/48)
+* kqueue: cleanup internal watch before sending remove event [#51](https://github.com/fsnotify/fsnotify/issues/51)
+
+## v1.0.4 / 2014-09-07
+
+* kqueue: add dragonfly to the build tags.
+* Rename source code files, rearrange code so exported APIs are at the top.
+* Add done channel to example code. [#37](https://github.com/fsnotify/fsnotify/pull/37) (thanks @chenyukang)
+
+## v1.0.3 / 2014-08-19
+
+* [Fix] Windows MOVED_TO now translates to Create like on BSD and Linux. [#36](https://github.com/fsnotify/fsnotify/issues/36)
+
+## v1.0.2 / 2014-08-17
+
+* [Fix] Missing create events on OS X. [#14](https://github.com/fsnotify/fsnotify/issues/14) (thanks @zhsso)
+* [Fix] Make ./path and path equivalent. (thanks @zhsso)
+
+## v1.0.0 / 2014-08-15
+
+* [API] Remove AddWatch on Windows, use Add.
+* Improve documentation for exported identifiers. [#30](https://github.com/fsnotify/fsnotify/issues/30)
+* Minor updates based on feedback from golint.
+
+## dev / 2014-07-09
+
+* Moved to [github.com/fsnotify/fsnotify](https://github.com/fsnotify/fsnotify).
+* Use os.NewSyscallError instead of returning errno (thanks @hariharan-uno)
+
+## dev / 2014-07-04
+
+* kqueue: fix incorrect mutex used in Close()
+* Update example to demonstrate usage of Op.
+
+## dev / 2014-06-28
+
+* [API] Don't set the Write Op for attribute notifications [#4](https://github.com/fsnotify/fsnotify/issues/4)
+* Fix for String() method on Event (thanks Alex Brainman)
+* Don't build on Plan 9 or Solaris (thanks @4ad)
+
+## dev / 2014-06-21
+
+* Events channel of type Event rather than *Event.
+* [internal] use syscall constants directly for inotify and kqueue.
+* [internal] kqueue: rename events to kevents and fileEvent to event.
+
+## dev / 2014-06-19
+
+* Go 1.3+ required on Windows (uses syscall.ERROR_MORE_DATA internally).
+* [internal] remove cookie from Event struct (unused).
+* [internal] Event struct has the same definition across every OS.
+* [internal] remove internal watch and removeWatch methods.
+
+## dev / 2014-06-12
+
+* [API] Renamed Watch() to Add() and RemoveWatch() to Remove().
+* [API] Pluralized channel names: Events and Errors.
+* [API] Renamed FileEvent struct to Event.
+* [API] Op constants replace methods like IsCreate().
+
+## dev / 2014-06-12
+
+* Fix data race on kevent buffer (thanks @tilaks) [#98](https://github.com/howeyc/fsnotify/pull/98)
+
+## dev / 2014-05-23
+
+* [API] Remove current implementation of WatchFlags.
+    * current implementation doesn't take advantage of OS for efficiency
+    * provides little benefit over filtering events as they are received, but has  extra bookkeeping and mutexes
+    * no tests for the current implementation
+    * not fully implemented on Windows [#93](https://github.com/howeyc/fsnotify/issues/93#issuecomment-39285195)
+
+## v0.9.3 / 2014-12-31
+
+* kqueue: cleanup internal watch before sending remove event [#51](https://github.com/fsnotify/fsnotify/issues/51)
+
+## v0.9.2 / 2014-08-17
+
+* [Backport] Fix missing create events on OS X. [#14](https://github.com/fsnotify/fsnotify/issues/14) (thanks @zhsso)
+
+## v0.9.1 / 2014-06-12
+
+* Fix data race on kevent buffer (thanks @tilaks) [#98](https://github.com/howeyc/fsnotify/pull/98)
+
+## v0.9.0 / 2014-01-17
+
+* IsAttrib() for events that only concern a file's metadata [#79][] (thanks @abustany)
+* [Fix] kqueue: fix deadlock [#77][] (thanks @cespare)
+* [NOTICE] Development has moved to `code.google.com/p/go.exp/fsnotify` in preparation for inclusion in the Go standard library.
+
+## v0.8.12 / 2013-11-13
+
+* [API] Remove FD_SET and friends from Linux adapter
+
+## v0.8.11 / 2013-11-02
+
+* [Doc] Add Changelog [#72][] (thanks @nathany)
+* [Doc] Spotlight and double modify events on OS X [#62][] (reported by @paulhammond)
+
+## v0.8.10 / 2013-10-19
+
+* [Fix] kqueue: remove file watches when parent directory is removed [#71][] (reported by @mdwhatcott)
+* [Fix] kqueue: race between Close and readEvents [#70][] (reported by @bernerdschaefer)
+* [Doc] specify OS-specific limits in README (thanks @debrando)
+
+## v0.8.9 / 2013-09-08
+
+* [Doc] Contributing (thanks @nathany)
+* [Doc] update package path in example code [#63][] (thanks @paulhammond)
+* [Doc] GoCI badge in README (Linux only) [#60][]
+* [Doc] Cross-platform testing with Vagrant  [#59][] (thanks @nathany)
+
+## v0.8.8 / 2013-06-17
+
+* [Fix] Windows: handle `ERROR_MORE_DATA` on Windows [#49][] (thanks @jbowtie)
+
+## v0.8.7 / 2013-06-03
+
+* [API] Make syscall flags internal
+* [Fix] inotify: ignore event changes
+* [Fix] race in symlink test [#45][] (reported by @srid)
+* [Fix] tests on Windows
+* lower case error messages
+
+## v0.8.6 / 2013-05-23
+
+* kqueue: Use EVT_ONLY flag on Darwin
+* [Doc] Update README with full example
+
+## v0.8.5 / 2013-05-09
+
+* [Fix] inotify: allow monitoring of "broken" symlinks (thanks @tsg)
+
+## v0.8.4 / 2013-04-07
+
+* [Fix] kqueue: watch all file events [#40][] (thanks @ChrisBuchholz)
+
+## v0.8.3 / 2013-03-13
+
+* [Fix] inoitfy/kqueue memory leak [#36][] (reported by @nbkolchin)
+* [Fix] kqueue: use fsnFlags for watching a directory [#33][] (reported by @nbkolchin)
+
+## v0.8.2 / 2013-02-07
+
+* [Doc] add Authors
+* [Fix] fix data races for map access [#29][] (thanks @fsouza)
+
+## v0.8.1 / 2013-01-09
+
+* [Fix] Windows path separators
+* [Doc] BSD License
+
+## v0.8.0 / 2012-11-09
+
+* kqueue: directory watching improvements (thanks @vmirage)
+* inotify: add `IN_MOVED_TO` [#25][] (requested by @cpisto)
+* [Fix] kqueue: deleting watched directory [#24][] (reported by @jakerr)
+
+## v0.7.4 / 2012-10-09
+
+* [Fix] inotify: fixes from https://codereview.appspot.com/5418045/ (ugorji)
+* [Fix] kqueue: preserve watch flags when watching for delete [#21][] (reported by @robfig)
+* [Fix] kqueue: watch the directory even if it isn't a new watch (thanks @robfig)
+* [Fix] kqueue: modify after recreation of file
+
+## v0.7.3 / 2012-09-27
+
+* [Fix] kqueue: watch with an existing folder inside the watched folder (thanks @vmirage)
+* [Fix] kqueue: no longer get duplicate CREATE events
+
+## v0.7.2 / 2012-09-01
+
+* kqueue: events for created directories
+
+## v0.7.1 / 2012-07-14
+
+* [Fix] for renaming files
+
+## v0.7.0 / 2012-07-02
+
+* [Feature] FSNotify flags
+* [Fix] inotify: Added file name back to event path
+
+## v0.6.0 / 2012-06-06
+
+* kqueue: watch files after directory created (thanks @tmc)
+
+## v0.5.1 / 2012-05-22
+
+* [Fix] inotify: remove all watches before Close()
+
+## v0.5.0 / 2012-05-03
+
+* [API] kqueue: return errors during watch instead of sending over channel
+* kqueue: match symlink behavior on Linux
+* inotify: add `DELETE_SELF` (requested by @taralx)
+* [Fix] kqueue: handle EINTR (reported by @robfig)
+* [Doc] Godoc example [#1][] (thanks @davecheney)
+
+## v0.4.0 / 2012-03-30
+
+* Go 1 released: build with go tool
+* [Feature] Windows support using winfsnotify
+* Windows does not have attribute change notifications
+* Roll attribute notifications into IsModify
+
+## v0.3.0 / 2012-02-19
+
+* kqueue: add files when watch directory
+
+## v0.2.0 / 2011-12-30
+
+* update to latest Go weekly code
+
+## v0.1.0 / 2011-10-19
+
+* kqueue: add watch on file creation to match inotify
+* kqueue: create file event
+* inotify: ignore `IN_IGNORED` events
+* event String()
+* linux: common FileEvent functions
+* initial commit
+
+[#79]: https://github.com/howeyc/fsnotify/pull/79
+[#77]: https://github.com/howeyc/fsnotify/pull/77
+[#72]: https://github.com/howeyc/fsnotify/issues/72
+[#71]: https://github.com/howeyc/fsnotify/issues/71
+[#70]: https://github.com/howeyc/fsnotify/issues/70
+[#63]: https://github.com/howeyc/fsnotify/issues/63
+[#62]: https://github.com/howeyc/fsnotify/issues/62
+[#60]: https://github.com/howeyc/fsnotify/issues/60
+[#59]: https://github.com/howeyc/fsnotify/issues/59
+[#49]: https://github.com/howeyc/fsnotify/issues/49
+[#45]: https://github.com/howeyc/fsnotify/issues/45
+[#40]: https://github.com/howeyc/fsnotify/issues/40
+[#36]: https://github.com/howeyc/fsnotify/issues/36
+[#33]: https://github.com/howeyc/fsnotify/issues/33
+[#29]: https://github.com/howeyc/fsnotify/issues/29
+[#25]: https://github.com/howeyc/fsnotify/issues/25
+[#24]: https://github.com/howeyc/fsnotify/issues/24
+[#21]: https://github.com/howeyc/fsnotify/issues/21
diff --git a/vendor/gopkg.in/fsnotify.v1/CONTRIBUTING.md b/vendor/gopkg.in/fsnotify.v1/CONTRIBUTING.md
new file mode 100644
index 000000000..617e45a06
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/CONTRIBUTING.md
@@ -0,0 +1,77 @@
+# Contributing
+
+## Issues
+
+* Request features and report bugs using the [GitHub Issue Tracker](https://github.com/fsnotify/fsnotify/issues).
+* Please indicate the platform you are using fsnotify on.
+* A code example to reproduce the problem is appreciated.
+
+## Pull Requests
+
+### Contributor License Agreement
+
+fsnotify is derived from code in the [golang.org/x/exp](https://godoc.org/golang.org/x/exp) package and it may be included [in the standard library](https://github.com/fsnotify/fsnotify/issues/1) in the future. Therefore fsnotify carries the same [LICENSE](https://github.com/fsnotify/fsnotify/blob/master/LICENSE) as Go. Contributors retain their copyright, so you need to fill out a short form before we can accept your contribution: [Google Individual Contributor License Agreement](https://developers.google.com/open-source/cla/individual).
+
+Please indicate that you have signed the CLA in your pull request.
+
+### How fsnotify is Developed
+
+* Development is done on feature branches.
+* Tests are run on BSD, Linux, OS X and Windows.
+* Pull requests are reviewed and [applied to master][am] using [hub][].
+  * Maintainers may modify or squash commits rather than asking contributors to.
+* To issue a new release, the maintainers will:
+  * Update the CHANGELOG
+  * Tag a version, which will become available through gopkg.in.
+ 
+### How to Fork
+
+For smooth sailing, always use the original import path. Installing with `go get` makes this easy. 
+
+1. Install from GitHub (`go get -u github.com/fsnotify/fsnotify`)
+2. Create your feature branch (`git checkout -b my-new-feature`)
+3. Ensure everything works and the tests pass (see below)
+4. Commit your changes (`git commit -am 'Add some feature'`)
+
+Contribute upstream:
+
+1. Fork fsnotify on GitHub
+2. Add your remote (`git remote add fork git@github.com:mycompany/repo.git`)
+3. Push to the branch (`git push fork my-new-feature`)
+4. Create a new Pull Request on GitHub
+
+This workflow is [thoroughly explained by Katrina Owen](https://blog.splice.com/contributing-open-source-git-repositories-go/).
+
+### Testing
+
+fsnotify uses build tags to compile different code on Linux, BSD, OS X, and Windows.
+
+Before doing a pull request, please do your best to test your changes on multiple platforms, and list which platforms you were able/unable to test on.
+
+To aid in cross-platform testing there is a Vagrantfile for Linux and BSD.
+
+* Install [Vagrant](http://www.vagrantup.com/) and [VirtualBox](https://www.virtualbox.org/)
+* Setup [Vagrant Gopher](https://github.com/nathany/vagrant-gopher) in your `src` folder.
+* Run `vagrant up` from the project folder. You can also setup just one box with `vagrant up linux` or `vagrant up bsd` (note: the BSD box doesn't support Windows hosts at this time, and NFS may prompt for your host OS password)
+* Once setup, you can run the test suite on a given OS with a single command `vagrant ssh linux -c 'cd fsnotify/fsnotify; go test'`.
+* When you're done, you will want to halt or destroy the Vagrant boxes.
+
+Notice: fsnotify file system events won't trigger in shared folders. The tests get around this limitation by using the /tmp directory.
+
+Right now there is no equivalent solution for Windows and OS X, but there are Windows VMs [freely available from Microsoft](http://www.modern.ie/en-us/virtualization-tools#downloads).
+
+### Maintainers
+
+Help maintaining fsnotify is welcome. To be a maintainer:
+
+* Submit a pull request and sign the CLA as above.
+* You must be able to run the test suite on Mac, Windows, Linux and BSD.
+
+To keep master clean, the fsnotify project uses the "apply mail" workflow outlined in Nathaniel Talbott's post ["Merge pull request" Considered Harmful][am]. This requires installing [hub][].
+
+All code changes should be internal pull requests.
+
+Releases are tagged using [Semantic Versioning](http://semver.org/).
+
+[hub]: https://github.com/github/hub
+[am]: http://blog.spreedly.com/2014/06/24/merge-pull-request-considered-harmful/#.VGa5yZPF_Zs
diff --git a/vendor/gopkg.in/fsnotify.v1/LICENSE b/vendor/gopkg.in/fsnotify.v1/LICENSE
new file mode 100644
index 000000000..f21e54080
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/LICENSE
@@ -0,0 +1,28 @@
+Copyright (c) 2012 The Go Authors. All rights reserved.
+Copyright (c) 2012 fsnotify Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/gopkg.in/fsnotify.v1/README.md b/vendor/gopkg.in/fsnotify.v1/README.md
new file mode 100644
index 000000000..5ebce86eb
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/README.md
@@ -0,0 +1,50 @@
+# File system notifications for Go
+
+[![GoDoc](https://godoc.org/github.com/fsnotify/fsnotify?status.svg)](https://godoc.org/github.com/fsnotify/fsnotify) [![Go Report Card](https://goreportcard.com/badge/github.com/fsnotify/fsnotify)](https://goreportcard.com/report/github.com/fsnotify/fsnotify) [![Coverage](http://gocover.io/_badge/github.com/fsnotify/fsnotify)](http://gocover.io/github.com/fsnotify/fsnotify) 
+
+fsnotify utilizes [golang.org/x/sys](https://godoc.org/golang.org/x/sys) rather than `syscall` from the standard library. Ensure you have the latest version installed by running:
+
+```console
+go get -u golang.org/x/sys/...
+```
+
+Cross platform: Windows, Linux, BSD and OS X.
+
+|Adapter   |OS        |Status    |
+|----------|----------|----------|
+|inotify   |Linux 2.6.27 or later, Android\*|Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify)|
+|kqueue    |BSD, OS X, iOS\*|Supported [![Build Status](https://travis-ci.org/fsnotify/fsnotify.svg?branch=master)](https://travis-ci.org/fsnotify/fsnotify)|
+|ReadDirectoryChangesW|Windows|Supported [![Build status](https://ci.appveyor.com/api/projects/status/ivwjubaih4r0udeh/branch/master?svg=true)](https://ci.appveyor.com/project/NathanYoungman/fsnotify/branch/master)|
+|FSEvents  |OS X          |[Planned](https://github.com/fsnotify/fsnotify/issues/11)|
+|FEN       |Solaris 11    |[In Progress](https://github.com/fsnotify/fsnotify/issues/12)|
+|fanotify  |Linux 2.6.37+ | |
+|USN Journals |Windows    |[Maybe](https://github.com/fsnotify/fsnotify/issues/53)|
+|Polling   |*All*         |[Maybe](https://github.com/fsnotify/fsnotify/issues/9)|
+
+\* Android and iOS are untested.
+
+Please see [the documentation](https://godoc.org/github.com/fsnotify/fsnotify) for usage. Consult the [Wiki](https://github.com/fsnotify/fsnotify/wiki) for the FAQ and further information.
+
+## API stability
+
+fsnotify is a fork of [howeyc/fsnotify](https://godoc.org/github.com/howeyc/fsnotify) with a new API as of v1.0. The API is based on [this design document](http://goo.gl/MrYxyA). 
+
+All [releases](https://github.com/fsnotify/fsnotify/releases) are tagged based on [Semantic Versioning](http://semver.org/). Further API changes are [planned](https://github.com/fsnotify/fsnotify/milestones), and will be tagged with a new major revision number.
+
+Go 1.6 supports dependencies located in the `vendor/` folder. Unless you are creating a library, it is recommended that you copy fsnotify into `vendor/github.com/fsnotify/fsnotify` within your project, and likewise for `golang.org/x/sys`.
+
+## Contributing
+
+Please refer to [CONTRIBUTING][] before opening an issue or pull request.
+
+## Example
+
+See [example_test.go](https://github.com/fsnotify/fsnotify/blob/master/example_test.go).
+
+[contributing]: https://github.com/fsnotify/fsnotify/blob/master/CONTRIBUTING.md
+
+## Related Projects
+
+* [notify](https://github.com/rjeczalik/notify)
+* [fsevents](https://github.com/fsnotify/fsevents)
+
diff --git a/vendor/gopkg.in/fsnotify.v1/fen.go b/vendor/gopkg.in/fsnotify.v1/fen.go
new file mode 100644
index 000000000..ced39cb88
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/fen.go
@@ -0,0 +1,37 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build solaris
+
+package fsnotify
+
+import (
+	"errors"
+)
+
+// Watcher watches a set of files, delivering events to a channel.
+type Watcher struct {
+	Events chan Event
+	Errors chan error
+}
+
+// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
+func NewWatcher() (*Watcher, error) {
+	return nil, errors.New("FEN based watcher not yet supported for fsnotify\n")
+}
+
+// Close removes all watches and closes the events channel.
+func (w *Watcher) Close() error {
+	return nil
+}
+
+// Add starts watching the named file or directory (non-recursively).
+func (w *Watcher) Add(name string) error {
+	return nil
+}
+
+// Remove stops watching the the named file or directory (non-recursively).
+func (w *Watcher) Remove(name string) error {
+	return nil
+}
diff --git a/vendor/gopkg.in/fsnotify.v1/fsnotify.go b/vendor/gopkg.in/fsnotify.v1/fsnotify.go
new file mode 100644
index 000000000..d1d39a0eb
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/fsnotify.go
@@ -0,0 +1,62 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !plan9
+
+// Package fsnotify provides a platform-independent interface for file system notifications.
+package fsnotify
+
+import (
+	"bytes"
+	"fmt"
+)
+
+// Event represents a single file system notification.
+type Event struct {
+	Name string // Relative path to the file or directory.
+	Op   Op     // File operation that triggered the event.
+}
+
+// Op describes a set of file operations.
+type Op uint32
+
+// These are the generalized file operations that can trigger a notification.
+const (
+	Create Op = 1 << iota
+	Write
+	Remove
+	Rename
+	Chmod
+)
+
+// String returns a string representation of the event in the form
+// "file: REMOVE|WRITE|..."
+func (e Event) String() string {
+	// Use a buffer for efficient string concatenation
+	var buffer bytes.Buffer
+
+	if e.Op&Create == Create {
+		buffer.WriteString("|CREATE")
+	}
+	if e.Op&Remove == Remove {
+		buffer.WriteString("|REMOVE")
+	}
+	if e.Op&Write == Write {
+		buffer.WriteString("|WRITE")
+	}
+	if e.Op&Rename == Rename {
+		buffer.WriteString("|RENAME")
+	}
+	if e.Op&Chmod == Chmod {
+		buffer.WriteString("|CHMOD")
+	}
+
+	// If buffer remains empty, return no event names
+	if buffer.Len() == 0 {
+		return fmt.Sprintf("%q: ", e.Name)
+	}
+
+	// Return a list of event names, with leading pipe character stripped
+	return fmt.Sprintf("%q: %s", e.Name, buffer.String()[1:])
+}
diff --git a/vendor/gopkg.in/fsnotify.v1/inotify.go b/vendor/gopkg.in/fsnotify.v1/inotify.go
new file mode 100644
index 000000000..9700df55e
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/inotify.go
@@ -0,0 +1,325 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+
+package fsnotify
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+// Watcher watches a set of files, delivering events to a channel.
+type Watcher struct {
+	Events   chan Event
+	Errors   chan error
+	mu       sync.Mutex // Map access
+	cv       *sync.Cond // sync removing on rm_watch with IN_IGNORE
+	fd       int
+	poller   *fdPoller
+	watches  map[string]*watch // Map of inotify watches (key: path)
+	paths    map[int]string    // Map of watched paths (key: watch descriptor)
+	done     chan struct{}     // Channel for sending a "quit message" to the reader goroutine
+	doneResp chan struct{}     // Channel to respond to Close
+}
+
+// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
+func NewWatcher() (*Watcher, error) {
+	// Create inotify fd
+	fd, errno := unix.InotifyInit()
+	if fd == -1 {
+		return nil, errno
+	}
+	// Create epoll
+	poller, err := newFdPoller(fd)
+	if err != nil {
+		unix.Close(fd)
+		return nil, err
+	}
+	w := &Watcher{
+		fd:       fd,
+		poller:   poller,
+		watches:  make(map[string]*watch),
+		paths:    make(map[int]string),
+		Events:   make(chan Event),
+		Errors:   make(chan error),
+		done:     make(chan struct{}),
+		doneResp: make(chan struct{}),
+	}
+	w.cv = sync.NewCond(&w.mu)
+
+	go w.readEvents()
+	return w, nil
+}
+
+func (w *Watcher) isClosed() bool {
+	select {
+	case <-w.done:
+		return true
+	default:
+		return false
+	}
+}
+
+// Close removes all watches and closes the events channel.
+func (w *Watcher) Close() error {
+	if w.isClosed() {
+		return nil
+	}
+
+	// Send 'close' signal to goroutine, and set the Watcher to closed.
+	close(w.done)
+
+	// Wake up goroutine
+	w.poller.wake()
+
+	// Wait for goroutine to close
+	<-w.doneResp
+
+	return nil
+}
+
+// Add starts watching the named file or directory (non-recursively).
+func (w *Watcher) Add(name string) error {
+	name = filepath.Clean(name)
+	if w.isClosed() {
+		return errors.New("inotify instance already closed")
+	}
+
+	const agnosticEvents = unix.IN_MOVED_TO | unix.IN_MOVED_FROM |
+		unix.IN_CREATE | unix.IN_ATTRIB | unix.IN_MODIFY |
+		unix.IN_MOVE_SELF | unix.IN_DELETE | unix.IN_DELETE_SELF
+
+	var flags uint32 = agnosticEvents
+
+	w.mu.Lock()
+	watchEntry, found := w.watches[name]
+	w.mu.Unlock()
+	if found {
+		watchEntry.flags |= flags
+		flags |= unix.IN_MASK_ADD
+	}
+	wd, errno := unix.InotifyAddWatch(w.fd, name, flags)
+	if wd == -1 {
+		return errno
+	}
+
+	w.mu.Lock()
+	w.watches[name] = &watch{wd: uint32(wd), flags: flags}
+	w.paths[wd] = name
+	w.mu.Unlock()
+
+	return nil
+}
+
+// Remove stops watching the named file or directory (non-recursively).
+func (w *Watcher) Remove(name string) error {
+	name = filepath.Clean(name)
+
+	// Fetch the watch.
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	watch, ok := w.watches[name]
+
+	// Remove it from inotify.
+	if !ok {
+		return fmt.Errorf("can't remove non-existent inotify watch for: %s", name)
+	}
+	// inotify_rm_watch will return EINVAL if the file has been deleted;
+	// the inotify will already have been removed.
+	// watches and pathes are deleted in ignoreLinux() implicitly and asynchronously
+	// by calling inotify_rm_watch() below. e.g. readEvents() goroutine receives IN_IGNORE
+	// so that EINVAL means that the wd is being rm_watch()ed or its file removed
+	// by another thread and we have not received IN_IGNORE event.
+	success, errno := unix.InotifyRmWatch(w.fd, watch.wd)
+	if success == -1 {
+		// TODO: Perhaps it's not helpful to return an error here in every case.
+		// the only two possible errors are:
+		// EBADF, which happens when w.fd is not a valid file descriptor of any kind.
+		// EINVAL, which is when fd is not an inotify descriptor or wd is not a valid watch descriptor.
+		// Watch descriptors are invalidated when they are removed explicitly or implicitly;
+		// explicitly by inotify_rm_watch, implicitly when the file they are watching is deleted.
+		return errno
+	}
+
+	// wait until ignoreLinux() deleting maps
+	exists := true
+	for exists {
+		w.cv.Wait()
+		_, exists = w.watches[name]
+	}
+
+	return nil
+}
+
+type watch struct {
+	wd    uint32 // Watch descriptor (as returned by the inotify_add_watch() syscall)
+	flags uint32 // inotify flags of this watch (see inotify(7) for the list of valid flags)
+}
+
+// readEvents reads from the inotify file descriptor, converts the
+// received events into Event objects and sends them via the Events channel
+func (w *Watcher) readEvents() {
+	var (
+		buf   [unix.SizeofInotifyEvent * 4096]byte // Buffer for a maximum of 4096 raw events
+		n     int                                  // Number of bytes read with read()
+		errno error                                // Syscall errno
+		ok    bool                                 // For poller.wait
+	)
+
+	defer close(w.doneResp)
+	defer close(w.Errors)
+	defer close(w.Events)
+	defer unix.Close(w.fd)
+	defer w.poller.close()
+
+	for {
+		// See if we have been closed.
+		if w.isClosed() {
+			return
+		}
+
+		ok, errno = w.poller.wait()
+		if errno != nil {
+			select {
+			case w.Errors <- errno:
+			case <-w.done:
+				return
+			}
+			continue
+		}
+
+		if !ok {
+			continue
+		}
+
+		n, errno = unix.Read(w.fd, buf[:])
+		// If a signal interrupted execution, see if we've been asked to close, and try again.
+		// http://man7.org/linux/man-pages/man7/signal.7.html :
+		// "Before Linux 3.8, reads from an inotify(7) file descriptor were not restartable"
+		if errno == unix.EINTR {
+			continue
+		}
+
+		// unix.Read might have been woken up by Close. If so, we're done.
+		if w.isClosed() {
+			return
+		}
+
+		if n < unix.SizeofInotifyEvent {
+			var err error
+			if n == 0 {
+				// If EOF is received. This should really never happen.
+				err = io.EOF
+			} else if n < 0 {
+				// If an error occurred while reading.
+				err = errno
+			} else {
+				// Read was too short.
+				err = errors.New("notify: short read in readEvents()")
+			}
+			select {
+			case w.Errors <- err:
+			case <-w.done:
+				return
+			}
+			continue
+		}
+
+		var offset uint32
+		// We don't know how many events we just read into the buffer
+		// While the offset points to at least one whole event...
+		for offset <= uint32(n-unix.SizeofInotifyEvent) {
+			// Point "raw" to the event in the buffer
+			raw := (*unix.InotifyEvent)(unsafe.Pointer(&buf[offset]))
+
+			mask := uint32(raw.Mask)
+			nameLen := uint32(raw.Len)
+			// If the event happened to the watched directory or the watched file, the kernel
+			// doesn't append the filename to the event, but we would like to always fill the
+			// the "Name" field with a valid filename. We retrieve the path of the watch from
+			// the "paths" map.
+			w.mu.Lock()
+			name := w.paths[int(raw.Wd)]
+			w.mu.Unlock()
+			if nameLen > 0 {
+				// Point "bytes" at the first byte of the filename
+				bytes := (*[unix.PathMax]byte)(unsafe.Pointer(&buf[offset+unix.SizeofInotifyEvent]))
+				// The filename is padded with NULL bytes. TrimRight() gets rid of those.
+				name += "/" + strings.TrimRight(string(bytes[0:nameLen]), "\000")
+			}
+
+			event := newEvent(name, mask)
+
+			// Send the events that are not ignored on the events channel
+			if !event.ignoreLinux(w, raw.Wd, mask) {
+				select {
+				case w.Events <- event:
+				case <-w.done:
+					return
+				}
+			}
+
+			// Move to the next event in the buffer
+			offset += unix.SizeofInotifyEvent + nameLen
+		}
+	}
+}
+
+// Certain types of events can be "ignored" and not sent over the Events
+// channel. Such as events marked ignore by the kernel, or MODIFY events
+// against files that do not exist.
+func (e *Event) ignoreLinux(w *Watcher, wd int32, mask uint32) bool {
+	// Ignore anything the inotify API says to ignore
+	if mask&unix.IN_IGNORED == unix.IN_IGNORED {
+		w.mu.Lock()
+		defer w.mu.Unlock()
+		name := w.paths[int(wd)]
+		delete(w.paths, int(wd))
+		delete(w.watches, name)
+		w.cv.Broadcast()
+		return true
+	}
+
+	// If the event is not a DELETE or RENAME, the file must exist.
+	// Otherwise the event is ignored.
+	// *Note*: this was put in place because it was seen that a MODIFY
+	// event was sent after the DELETE. This ignores that MODIFY and
+	// assumes a DELETE will come or has come if the file doesn't exist.
+	if !(e.Op&Remove == Remove || e.Op&Rename == Rename) {
+		_, statErr := os.Lstat(e.Name)
+		return os.IsNotExist(statErr)
+	}
+	return false
+}
+
+// newEvent returns an platform-independent Event based on an inotify mask.
+func newEvent(name string, mask uint32) Event {
+	e := Event{Name: name}
+	if mask&unix.IN_CREATE == unix.IN_CREATE || mask&unix.IN_MOVED_TO == unix.IN_MOVED_TO {
+		e.Op |= Create
+	}
+	if mask&unix.IN_DELETE_SELF == unix.IN_DELETE_SELF || mask&unix.IN_DELETE == unix.IN_DELETE {
+		e.Op |= Remove
+	}
+	if mask&unix.IN_MODIFY == unix.IN_MODIFY {
+		e.Op |= Write
+	}
+	if mask&unix.IN_MOVE_SELF == unix.IN_MOVE_SELF || mask&unix.IN_MOVED_FROM == unix.IN_MOVED_FROM {
+		e.Op |= Rename
+	}
+	if mask&unix.IN_ATTRIB == unix.IN_ATTRIB {
+		e.Op |= Chmod
+	}
+	return e
+}
diff --git a/vendor/gopkg.in/fsnotify.v1/inotify_poller.go b/vendor/gopkg.in/fsnotify.v1/inotify_poller.go
new file mode 100644
index 000000000..cc7db4b22
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/inotify_poller.go
@@ -0,0 +1,187 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+
+package fsnotify
+
+import (
+	"errors"
+
+	"golang.org/x/sys/unix"
+)
+
+type fdPoller struct {
+	fd   int    // File descriptor (as returned by the inotify_init() syscall)
+	epfd int    // Epoll file descriptor
+	pipe [2]int // Pipe for waking up
+}
+
+func emptyPoller(fd int) *fdPoller {
+	poller := new(fdPoller)
+	poller.fd = fd
+	poller.epfd = -1
+	poller.pipe[0] = -1
+	poller.pipe[1] = -1
+	return poller
+}
+
+// Create a new inotify poller.
+// This creates an inotify handler, and an epoll handler.
+func newFdPoller(fd int) (*fdPoller, error) {
+	var errno error
+	poller := emptyPoller(fd)
+	defer func() {
+		if errno != nil {
+			poller.close()
+		}
+	}()
+	poller.fd = fd
+
+	// Create epoll fd
+	poller.epfd, errno = unix.EpollCreate1(0)
+	if poller.epfd == -1 {
+		return nil, errno
+	}
+	// Create pipe; pipe[0] is the read end, pipe[1] the write end.
+	errno = unix.Pipe2(poller.pipe[:], unix.O_NONBLOCK)
+	if errno != nil {
+		return nil, errno
+	}
+
+	// Register inotify fd with epoll
+	event := unix.EpollEvent{
+		Fd:     int32(poller.fd),
+		Events: unix.EPOLLIN,
+	}
+	errno = unix.EpollCtl(poller.epfd, unix.EPOLL_CTL_ADD, poller.fd, &event)
+	if errno != nil {
+		return nil, errno
+	}
+
+	// Register pipe fd with epoll
+	event = unix.EpollEvent{
+		Fd:     int32(poller.pipe[0]),
+		Events: unix.EPOLLIN,
+	}
+	errno = unix.EpollCtl(poller.epfd, unix.EPOLL_CTL_ADD, poller.pipe[0], &event)
+	if errno != nil {
+		return nil, errno
+	}
+
+	return poller, nil
+}
+
+// Wait using epoll.
+// Returns true if something is ready to be read,
+// false if there is not.
+func (poller *fdPoller) wait() (bool, error) {
+	// 3 possible events per fd, and 2 fds, makes a maximum of 6 events.
+	// I don't know whether epoll_wait returns the number of events returned,
+	// or the total number of events ready.
+	// I decided to catch both by making the buffer one larger than the maximum.
+	events := make([]unix.EpollEvent, 7)
+	for {
+		n, errno := unix.EpollWait(poller.epfd, events, -1)
+		if n == -1 {
+			if errno == unix.EINTR {
+				continue
+			}
+			return false, errno
+		}
+		if n == 0 {
+			// If there are no events, try again.
+			continue
+		}
+		if n > 6 {
+			// This should never happen. More events were returned than should be possible.
+			return false, errors.New("epoll_wait returned more events than I know what to do with")
+		}
+		ready := events[:n]
+		epollhup := false
+		epollerr := false
+		epollin := false
+		for _, event := range ready {
+			if event.Fd == int32(poller.fd) {
+				if event.Events&unix.EPOLLHUP != 0 {
+					// This should not happen, but if it does, treat it as a wakeup.
+					epollhup = true
+				}
+				if event.Events&unix.EPOLLERR != 0 {
+					// If an error is waiting on the file descriptor, we should pretend
+					// something is ready to read, and let unix.Read pick up the error.
+					epollerr = true
+				}
+				if event.Events&unix.EPOLLIN != 0 {
+					// There is data to read.
+					epollin = true
+				}
+			}
+			if event.Fd == int32(poller.pipe[0]) {
+				if event.Events&unix.EPOLLHUP != 0 {
+					// Write pipe descriptor was closed, by us. This means we're closing down the
+					// watcher, and we should wake up.
+				}
+				if event.Events&unix.EPOLLERR != 0 {
+					// If an error is waiting on the pipe file descriptor.
+					// This is an absolute mystery, and should never ever happen.
+					return false, errors.New("Error on the pipe descriptor.")
+				}
+				if event.Events&unix.EPOLLIN != 0 {
+					// This is a regular wakeup, so we have to clear the buffer.
+					err := poller.clearWake()
+					if err != nil {
+						return false, err
+					}
+				}
+			}
+		}
+
+		if epollhup || epollerr || epollin {
+			return true, nil
+		}
+		return false, nil
+	}
+}
+
+// Close the write end of the poller.
+func (poller *fdPoller) wake() error {
+	buf := make([]byte, 1)
+	n, errno := unix.Write(poller.pipe[1], buf)
+	if n == -1 {
+		if errno == unix.EAGAIN {
+			// Buffer is full, poller will wake.
+			return nil
+		}
+		return errno
+	}
+	return nil
+}
+
+func (poller *fdPoller) clearWake() error {
+	// You have to be woken up a LOT in order to get to 100!
+	buf := make([]byte, 100)
+	n, errno := unix.Read(poller.pipe[0], buf)
+	if n == -1 {
+		if errno == unix.EAGAIN {
+			// Buffer is empty, someone else cleared our wake.
+			return nil
+		}
+		return errno
+	}
+	return nil
+}
+
+// Close all poller file descriptors, but not the one passed to it.
+func (poller *fdPoller) close() {
+	if poller.pipe[1] != -1 {
+		unix.Close(poller.pipe[1])
+	}
+	if poller.pipe[0] != -1 {
+		unix.Close(poller.pipe[0])
+	}
+	if poller.epfd != -1 {
+		unix.Close(poller.epfd)
+	}
+}
diff --git a/vendor/gopkg.in/fsnotify.v1/kqueue.go b/vendor/gopkg.in/fsnotify.v1/kqueue.go
new file mode 100644
index 000000000..c2b4acb18
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/kqueue.go
@@ -0,0 +1,503 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build freebsd openbsd netbsd dragonfly darwin
+
+package fsnotify
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+
+	"golang.org/x/sys/unix"
+)
+
+// Watcher watches a set of files, delivering events to a channel.
+type Watcher struct {
+	Events chan Event
+	Errors chan error
+	done   chan bool // Channel for sending a "quit message" to the reader goroutine
+
+	kq int // File descriptor (as returned by the kqueue() syscall).
+
+	mu              sync.Mutex        // Protects access to watcher data
+	watches         map[string]int    // Map of watched file descriptors (key: path).
+	externalWatches map[string]bool   // Map of watches added by user of the library.
+	dirFlags        map[string]uint32 // Map of watched directories to fflags used in kqueue.
+	paths           map[int]pathInfo  // Map file descriptors to path names for processing kqueue events.
+	fileExists      map[string]bool   // Keep track of if we know this file exists (to stop duplicate create events).
+	isClosed        bool              // Set to true when Close() is first called
+}
+
+type pathInfo struct {
+	name  string
+	isDir bool
+}
+
+// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
+func NewWatcher() (*Watcher, error) {
+	kq, err := kqueue()
+	if err != nil {
+		return nil, err
+	}
+
+	w := &Watcher{
+		kq:              kq,
+		watches:         make(map[string]int),
+		dirFlags:        make(map[string]uint32),
+		paths:           make(map[int]pathInfo),
+		fileExists:      make(map[string]bool),
+		externalWatches: make(map[string]bool),
+		Events:          make(chan Event),
+		Errors:          make(chan error),
+		done:            make(chan bool),
+	}
+
+	go w.readEvents()
+	return w, nil
+}
+
+// Close removes all watches and closes the events channel.
+func (w *Watcher) Close() error {
+	w.mu.Lock()
+	if w.isClosed {
+		w.mu.Unlock()
+		return nil
+	}
+	w.isClosed = true
+	w.mu.Unlock()
+
+	// copy paths to remove while locked
+	w.mu.Lock()
+	var pathsToRemove = make([]string, 0, len(w.watches))
+	for name := range w.watches {
+		pathsToRemove = append(pathsToRemove, name)
+	}
+	w.mu.Unlock()
+	// unlock before calling Remove, which also locks
+
+	var err error
+	for _, name := range pathsToRemove {
+		if e := w.Remove(name); e != nil && err == nil {
+			err = e
+		}
+	}
+
+	// Send "quit" message to the reader goroutine:
+	w.done <- true
+
+	return nil
+}
+
+// Add starts watching the named file or directory (non-recursively).
+func (w *Watcher) Add(name string) error {
+	w.mu.Lock()
+	w.externalWatches[name] = true
+	w.mu.Unlock()
+	_, err := w.addWatch(name, noteAllEvents)
+	return err
+}
+
+// Remove stops watching the the named file or directory (non-recursively).
+func (w *Watcher) Remove(name string) error {
+	name = filepath.Clean(name)
+	w.mu.Lock()
+	watchfd, ok := w.watches[name]
+	w.mu.Unlock()
+	if !ok {
+		return fmt.Errorf("can't remove non-existent kevent watch for: %s", name)
+	}
+
+	const registerRemove = unix.EV_DELETE
+	if err := register(w.kq, []int{watchfd}, registerRemove, 0); err != nil {
+		return err
+	}
+
+	unix.Close(watchfd)
+
+	w.mu.Lock()
+	isDir := w.paths[watchfd].isDir
+	delete(w.watches, name)
+	delete(w.paths, watchfd)
+	delete(w.dirFlags, name)
+	w.mu.Unlock()
+
+	// Find all watched paths that are in this directory that are not external.
+	if isDir {
+		var pathsToRemove []string
+		w.mu.Lock()
+		for _, path := range w.paths {
+			wdir, _ := filepath.Split(path.name)
+			if filepath.Clean(wdir) == name {
+				if !w.externalWatches[path.name] {
+					pathsToRemove = append(pathsToRemove, path.name)
+				}
+			}
+		}
+		w.mu.Unlock()
+		for _, name := range pathsToRemove {
+			// Since these are internal, not much sense in propagating error
+			// to the user, as that will just confuse them with an error about
+			// a path they did not explicitly watch themselves.
+			w.Remove(name)
+		}
+	}
+
+	return nil
+}
+
+// Watch all events (except NOTE_EXTEND, NOTE_LINK, NOTE_REVOKE)
+const noteAllEvents = unix.NOTE_DELETE | unix.NOTE_WRITE | unix.NOTE_ATTRIB | unix.NOTE_RENAME
+
+// keventWaitTime to block on each read from kevent
+var keventWaitTime = durationToTimespec(100 * time.Millisecond)
+
+// addWatch adds name to the watched file set.
+// The flags are interpreted as described in kevent(2).
+// Returns the real path to the file which was added, if any, which may be different from the one passed in the case of symlinks.
+func (w *Watcher) addWatch(name string, flags uint32) (string, error) {
+	var isDir bool
+	// Make ./name and name equivalent
+	name = filepath.Clean(name)
+
+	w.mu.Lock()
+	if w.isClosed {
+		w.mu.Unlock()
+		return "", errors.New("kevent instance already closed")
+	}
+	watchfd, alreadyWatching := w.watches[name]
+	// We already have a watch, but we can still override flags.
+	if alreadyWatching {
+		isDir = w.paths[watchfd].isDir
+	}
+	w.mu.Unlock()
+
+	if !alreadyWatching {
+		fi, err := os.Lstat(name)
+		if err != nil {
+			return "", err
+		}
+
+		// Don't watch sockets.
+		if fi.Mode()&os.ModeSocket == os.ModeSocket {
+			return "", nil
+		}
+
+		// Don't watch named pipes.
+		if fi.Mode()&os.ModeNamedPipe == os.ModeNamedPipe {
+			return "", nil
+		}
+
+		// Follow Symlinks
+		// Unfortunately, Linux can add bogus symlinks to watch list without
+		// issue, and Windows can't do symlinks period (AFAIK). To  maintain
+		// consistency, we will act like everything is fine. There will simply
+		// be no file events for broken symlinks.
+		// Hence the returns of nil on errors.
+		if fi.Mode()&os.ModeSymlink == os.ModeSymlink {
+			name, err = filepath.EvalSymlinks(name)
+			if err != nil {
+				return "", nil
+			}
+
+			w.mu.Lock()
+			_, alreadyWatching = w.watches[name]
+			w.mu.Unlock()
+
+			if alreadyWatching {
+				return name, nil
+			}
+
+			fi, err = os.Lstat(name)
+			if err != nil {
+				return "", nil
+			}
+		}
+
+		watchfd, err = unix.Open(name, openMode, 0700)
+		if watchfd == -1 {
+			return "", err
+		}
+
+		isDir = fi.IsDir()
+	}
+
+	const registerAdd = unix.EV_ADD | unix.EV_CLEAR | unix.EV_ENABLE
+	if err := register(w.kq, []int{watchfd}, registerAdd, flags); err != nil {
+		unix.Close(watchfd)
+		return "", err
+	}
+
+	if !alreadyWatching {
+		w.mu.Lock()
+		w.watches[name] = watchfd
+		w.paths[watchfd] = pathInfo{name: name, isDir: isDir}
+		w.mu.Unlock()
+	}
+
+	if isDir {
+		// Watch the directory if it has not been watched before,
+		// or if it was watched before, but perhaps only a NOTE_DELETE (watchDirectoryFiles)
+		w.mu.Lock()
+
+		watchDir := (flags&unix.NOTE_WRITE) == unix.NOTE_WRITE &&
+			(!alreadyWatching || (w.dirFlags[name]&unix.NOTE_WRITE) != unix.NOTE_WRITE)
+		// Store flags so this watch can be updated later
+		w.dirFlags[name] = flags
+		w.mu.Unlock()
+
+		if watchDir {
+			if err := w.watchDirectoryFiles(name); err != nil {
+				return "", err
+			}
+		}
+	}
+	return name, nil
+}
+
+// readEvents reads from kqueue and converts the received kevents into
+// Event values that it sends down the Events channel.
+func (w *Watcher) readEvents() {
+	eventBuffer := make([]unix.Kevent_t, 10)
+
+	for {
+		// See if there is a message on the "done" channel
+		select {
+		case <-w.done:
+			err := unix.Close(w.kq)
+			if err != nil {
+				w.Errors <- err
+			}
+			close(w.Events)
+			close(w.Errors)
+			return
+		default:
+		}
+
+		// Get new events
+		kevents, err := read(w.kq, eventBuffer, &keventWaitTime)
+		// EINTR is okay, the syscall was interrupted before timeout expired.
+		if err != nil && err != unix.EINTR {
+			w.Errors <- err
+			continue
+		}
+
+		// Flush the events we received to the Events channel
+		for len(kevents) > 0 {
+			kevent := &kevents[0]
+			watchfd := int(kevent.Ident)
+			mask := uint32(kevent.Fflags)
+			w.mu.Lock()
+			path := w.paths[watchfd]
+			w.mu.Unlock()
+			event := newEvent(path.name, mask)
+
+			if path.isDir && !(event.Op&Remove == Remove) {
+				// Double check to make sure the directory exists. This can happen when
+				// we do a rm -fr on a recursively watched folders and we receive a
+				// modification event first but the folder has been deleted and later
+				// receive the delete event
+				if _, err := os.Lstat(event.Name); os.IsNotExist(err) {
+					// mark is as delete event
+					event.Op |= Remove
+				}
+			}
+
+			if event.Op&Rename == Rename || event.Op&Remove == Remove {
+				w.Remove(event.Name)
+				w.mu.Lock()
+				delete(w.fileExists, event.Name)
+				w.mu.Unlock()
+			}
+
+			if path.isDir && event.Op&Write == Write && !(event.Op&Remove == Remove) {
+				w.sendDirectoryChangeEvents(event.Name)
+			} else {
+				// Send the event on the Events channel
+				w.Events <- event
+			}
+
+			if event.Op&Remove == Remove {
+				// Look for a file that may have overwritten this.
+				// For example, mv f1 f2 will delete f2, then create f2.
+				if path.isDir {
+					fileDir := filepath.Clean(event.Name)
+					w.mu.Lock()
+					_, found := w.watches[fileDir]
+					w.mu.Unlock()
+					if found {
+						// make sure the directory exists before we watch for changes. When we
+						// do a recursive watch and perform rm -fr, the parent directory might
+						// have gone missing, ignore the missing directory and let the
+						// upcoming delete event remove the watch from the parent directory.
+						if _, err := os.Lstat(fileDir); err == nil {
+							w.sendDirectoryChangeEvents(fileDir)
+						}
+					}
+				} else {
+					filePath := filepath.Clean(event.Name)
+					if fileInfo, err := os.Lstat(filePath); err == nil {
+						w.sendFileCreatedEventIfNew(filePath, fileInfo)
+					}
+				}
+			}
+
+			// Move to next event
+			kevents = kevents[1:]
+		}
+	}
+}
+
+// newEvent returns an platform-independent Event based on kqueue Fflags.
+func newEvent(name string, mask uint32) Event {
+	e := Event{Name: name}
+	if mask&unix.NOTE_DELETE == unix.NOTE_DELETE {
+		e.Op |= Remove
+	}
+	if mask&unix.NOTE_WRITE == unix.NOTE_WRITE {
+		e.Op |= Write
+	}
+	if mask&unix.NOTE_RENAME == unix.NOTE_RENAME {
+		e.Op |= Rename
+	}
+	if mask&unix.NOTE_ATTRIB == unix.NOTE_ATTRIB {
+		e.Op |= Chmod
+	}
+	return e
+}
+
+func newCreateEvent(name string) Event {
+	return Event{Name: name, Op: Create}
+}
+
+// watchDirectoryFiles to mimic inotify when adding a watch on a directory
+func (w *Watcher) watchDirectoryFiles(dirPath string) error {
+	// Get all files
+	files, err := ioutil.ReadDir(dirPath)
+	if err != nil {
+		return err
+	}
+
+	for _, fileInfo := range files {
+		filePath := filepath.Join(dirPath, fileInfo.Name())
+		filePath, err = w.internalWatch(filePath, fileInfo)
+		if err != nil {
+			return err
+		}
+
+		w.mu.Lock()
+		w.fileExists[filePath] = true
+		w.mu.Unlock()
+	}
+
+	return nil
+}
+
+// sendDirectoryEvents searches the directory for newly created files
+// and sends them over the event channel. This functionality is to have
+// the BSD version of fsnotify match Linux inotify which provides a
+// create event for files created in a watched directory.
+func (w *Watcher) sendDirectoryChangeEvents(dirPath string) {
+	// Get all files
+	files, err := ioutil.ReadDir(dirPath)
+	if err != nil {
+		w.Errors <- err
+	}
+
+	// Search for new files
+	for _, fileInfo := range files {
+		filePath := filepath.Join(dirPath, fileInfo.Name())
+		err := w.sendFileCreatedEventIfNew(filePath, fileInfo)
+
+		if err != nil {
+			return
+		}
+	}
+}
+
+// sendFileCreatedEvent sends a create event if the file isn't already being tracked.
+func (w *Watcher) sendFileCreatedEventIfNew(filePath string, fileInfo os.FileInfo) (err error) {
+	w.mu.Lock()
+	_, doesExist := w.fileExists[filePath]
+	w.mu.Unlock()
+	if !doesExist {
+		// Send create event
+		w.Events <- newCreateEvent(filePath)
+	}
+
+	// like watchDirectoryFiles (but without doing another ReadDir)
+	filePath, err = w.internalWatch(filePath, fileInfo)
+	if err != nil {
+		return err
+	}
+
+	w.mu.Lock()
+	w.fileExists[filePath] = true
+	w.mu.Unlock()
+
+	return nil
+}
+
+func (w *Watcher) internalWatch(name string, fileInfo os.FileInfo) (string, error) {
+	if fileInfo.IsDir() {
+		// mimic Linux providing delete events for subdirectories
+		// but preserve the flags used if currently watching subdirectory
+		w.mu.Lock()
+		flags := w.dirFlags[name]
+		w.mu.Unlock()
+
+		flags |= unix.NOTE_DELETE | unix.NOTE_RENAME
+		return w.addWatch(name, flags)
+	}
+
+	// watch file to mimic Linux inotify
+	return w.addWatch(name, noteAllEvents)
+}
+
+// kqueue creates a new kernel event queue and returns a descriptor.
+func kqueue() (kq int, err error) {
+	kq, err = unix.Kqueue()
+	if kq == -1 {
+		return kq, err
+	}
+	return kq, nil
+}
+
+// register events with the queue
+func register(kq int, fds []int, flags int, fflags uint32) error {
+	changes := make([]unix.Kevent_t, len(fds))
+
+	for i, fd := range fds {
+		// SetKevent converts int to the platform-specific types:
+		unix.SetKevent(&changes[i], fd, unix.EVFILT_VNODE, flags)
+		changes[i].Fflags = fflags
+	}
+
+	// register the events
+	success, err := unix.Kevent(kq, changes, nil, nil)
+	if success == -1 {
+		return err
+	}
+	return nil
+}
+
+// read retrieves pending events, or waits until an event occurs.
+// A timeout of nil blocks indefinitely, while 0 polls the queue.
+func read(kq int, events []unix.Kevent_t, timeout *unix.Timespec) ([]unix.Kevent_t, error) {
+	n, err := unix.Kevent(kq, nil, events, timeout)
+	if err != nil {
+		return nil, err
+	}
+	return events[0:n], nil
+}
+
+// durationToTimespec prepares a timeout value
+func durationToTimespec(d time.Duration) unix.Timespec {
+	return unix.NsecToTimespec(d.Nanoseconds())
+}
diff --git a/vendor/gopkg.in/fsnotify.v1/open_mode_bsd.go b/vendor/gopkg.in/fsnotify.v1/open_mode_bsd.go
new file mode 100644
index 000000000..7d8de1451
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/open_mode_bsd.go
@@ -0,0 +1,11 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build freebsd openbsd netbsd dragonfly
+
+package fsnotify
+
+import "golang.org/x/sys/unix"
+
+const openMode = unix.O_NONBLOCK | unix.O_RDONLY
diff --git a/vendor/gopkg.in/fsnotify.v1/open_mode_darwin.go b/vendor/gopkg.in/fsnotify.v1/open_mode_darwin.go
new file mode 100644
index 000000000..9139e1716
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/open_mode_darwin.go
@@ -0,0 +1,12 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin
+
+package fsnotify
+
+import "golang.org/x/sys/unix"
+
+// note: this constant is not defined on BSD
+const openMode = unix.O_EVTONLY
diff --git a/vendor/gopkg.in/fsnotify.v1/windows.go b/vendor/gopkg.in/fsnotify.v1/windows.go
new file mode 100644
index 000000000..c836bdb3d
--- /dev/null
+++ b/vendor/gopkg.in/fsnotify.v1/windows.go
@@ -0,0 +1,561 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package fsnotify
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"sync"
+	"syscall"
+	"unsafe"
+)
+
+// Watcher watches a set of files, delivering events to a channel.
+type Watcher struct {
+	Events   chan Event
+	Errors   chan error
+	isClosed bool           // Set to true when Close() is first called
+	mu       sync.Mutex     // Map access
+	port     syscall.Handle // Handle to completion port
+	watches  watchMap       // Map of watches (key: i-number)
+	input    chan *input    // Inputs to the reader are sent on this channel
+	quit     chan chan<- error
+}
+
+// NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.
+func NewWatcher() (*Watcher, error) {
+	port, e := syscall.CreateIoCompletionPort(syscall.InvalidHandle, 0, 0, 0)
+	if e != nil {
+		return nil, os.NewSyscallError("CreateIoCompletionPort", e)
+	}
+	w := &Watcher{
+		port:    port,
+		watches: make(watchMap),
+		input:   make(chan *input, 1),
+		Events:  make(chan Event, 50),
+		Errors:  make(chan error),
+		quit:    make(chan chan<- error, 1),
+	}
+	go w.readEvents()
+	return w, nil
+}
+
+// Close removes all watches and closes the events channel.
+func (w *Watcher) Close() error {
+	if w.isClosed {
+		return nil
+	}
+	w.isClosed = true
+
+	// Send "quit" message to the reader goroutine
+	ch := make(chan error)
+	w.quit <- ch
+	if err := w.wakeupReader(); err != nil {
+		return err
+	}
+	return <-ch
+}
+
+// Add starts watching the named file or directory (non-recursively).
+func (w *Watcher) Add(name string) error {
+	if w.isClosed {
+		return errors.New("watcher already closed")
+	}
+	in := &input{
+		op:    opAddWatch,
+		path:  filepath.Clean(name),
+		flags: sysFSALLEVENTS,
+		reply: make(chan error),
+	}
+	w.input <- in
+	if err := w.wakeupReader(); err != nil {
+		return err
+	}
+	return <-in.reply
+}
+
+// Remove stops watching the the named file or directory (non-recursively).
+func (w *Watcher) Remove(name string) error {
+	in := &input{
+		op:    opRemoveWatch,
+		path:  filepath.Clean(name),
+		reply: make(chan error),
+	}
+	w.input <- in
+	if err := w.wakeupReader(); err != nil {
+		return err
+	}
+	return <-in.reply
+}
+
+const (
+	// Options for AddWatch
+	sysFSONESHOT = 0x80000000
+	sysFSONLYDIR = 0x1000000
+
+	// Events
+	sysFSACCESS     = 0x1
+	sysFSALLEVENTS  = 0xfff
+	sysFSATTRIB     = 0x4
+	sysFSCLOSE      = 0x18
+	sysFSCREATE     = 0x100
+	sysFSDELETE     = 0x200
+	sysFSDELETESELF = 0x400
+	sysFSMODIFY     = 0x2
+	sysFSMOVE       = 0xc0
+	sysFSMOVEDFROM  = 0x40
+	sysFSMOVEDTO    = 0x80
+	sysFSMOVESELF   = 0x800
+
+	// Special events
+	sysFSIGNORED   = 0x8000
+	sysFSQOVERFLOW = 0x4000
+)
+
+func newEvent(name string, mask uint32) Event {
+	e := Event{Name: name}
+	if mask&sysFSCREATE == sysFSCREATE || mask&sysFSMOVEDTO == sysFSMOVEDTO {
+		e.Op |= Create
+	}
+	if mask&sysFSDELETE == sysFSDELETE || mask&sysFSDELETESELF == sysFSDELETESELF {
+		e.Op |= Remove
+	}
+	if mask&sysFSMODIFY == sysFSMODIFY {
+		e.Op |= Write
+	}
+	if mask&sysFSMOVE == sysFSMOVE || mask&sysFSMOVESELF == sysFSMOVESELF || mask&sysFSMOVEDFROM == sysFSMOVEDFROM {
+		e.Op |= Rename
+	}
+	if mask&sysFSATTRIB == sysFSATTRIB {
+		e.Op |= Chmod
+	}
+	return e
+}
+
+const (
+	opAddWatch = iota
+	opRemoveWatch
+)
+
+const (
+	provisional uint64 = 1 << (32 + iota)
+)
+
+type input struct {
+	op    int
+	path  string
+	flags uint32
+	reply chan error
+}
+
+type inode struct {
+	handle syscall.Handle
+	volume uint32
+	index  uint64
+}
+
+type watch struct {
+	ov     syscall.Overlapped
+	ino    *inode            // i-number
+	path   string            // Directory path
+	mask   uint64            // Directory itself is being watched with these notify flags
+	names  map[string]uint64 // Map of names being watched and their notify flags
+	rename string            // Remembers the old name while renaming a file
+	buf    [4096]byte
+}
+
+type indexMap map[uint64]*watch
+type watchMap map[uint32]indexMap
+
+func (w *Watcher) wakeupReader() error {
+	e := syscall.PostQueuedCompletionStatus(w.port, 0, 0, nil)
+	if e != nil {
+		return os.NewSyscallError("PostQueuedCompletionStatus", e)
+	}
+	return nil
+}
+
+func getDir(pathname string) (dir string, err error) {
+	attr, e := syscall.GetFileAttributes(syscall.StringToUTF16Ptr(pathname))
+	if e != nil {
+		return "", os.NewSyscallError("GetFileAttributes", e)
+	}
+	if attr&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
+		dir = pathname
+	} else {
+		dir, _ = filepath.Split(pathname)
+		dir = filepath.Clean(dir)
+	}
+	return
+}
+
+func getIno(path string) (ino *inode, err error) {
+	h, e := syscall.CreateFile(syscall.StringToUTF16Ptr(path),
+		syscall.FILE_LIST_DIRECTORY,
+		syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE|syscall.FILE_SHARE_DELETE,
+		nil, syscall.OPEN_EXISTING,
+		syscall.FILE_FLAG_BACKUP_SEMANTICS|syscall.FILE_FLAG_OVERLAPPED, 0)
+	if e != nil {
+		return nil, os.NewSyscallError("CreateFile", e)
+	}
+	var fi syscall.ByHandleFileInformation
+	if e = syscall.GetFileInformationByHandle(h, &fi); e != nil {
+		syscall.CloseHandle(h)
+		return nil, os.NewSyscallError("GetFileInformationByHandle", e)
+	}
+	ino = &inode{
+		handle: h,
+		volume: fi.VolumeSerialNumber,
+		index:  uint64(fi.FileIndexHigh)<<32 | uint64(fi.FileIndexLow),
+	}
+	return ino, nil
+}
+
+// Must run within the I/O thread.
+func (m watchMap) get(ino *inode) *watch {
+	if i := m[ino.volume]; i != nil {
+		return i[ino.index]
+	}
+	return nil
+}
+
+// Must run within the I/O thread.
+func (m watchMap) set(ino *inode, watch *watch) {
+	i := m[ino.volume]
+	if i == nil {
+		i = make(indexMap)
+		m[ino.volume] = i
+	}
+	i[ino.index] = watch
+}
+
+// Must run within the I/O thread.
+func (w *Watcher) addWatch(pathname string, flags uint64) error {
+	dir, err := getDir(pathname)
+	if err != nil {
+		return err
+	}
+	if flags&sysFSONLYDIR != 0 && pathname != dir {
+		return nil
+	}
+	ino, err := getIno(dir)
+	if err != nil {
+		return err
+	}
+	w.mu.Lock()
+	watchEntry := w.watches.get(ino)
+	w.mu.Unlock()
+	if watchEntry == nil {
+		if _, e := syscall.CreateIoCompletionPort(ino.handle, w.port, 0, 0); e != nil {
+			syscall.CloseHandle(ino.handle)
+			return os.NewSyscallError("CreateIoCompletionPort", e)
+		}
+		watchEntry = &watch{
+			ino:   ino,
+			path:  dir,
+			names: make(map[string]uint64),
+		}
+		w.mu.Lock()
+		w.watches.set(ino, watchEntry)
+		w.mu.Unlock()
+		flags |= provisional
+	} else {
+		syscall.CloseHandle(ino.handle)
+	}
+	if pathname == dir {
+		watchEntry.mask |= flags
+	} else {
+		watchEntry.names[filepath.Base(pathname)] |= flags
+	}
+	if err = w.startRead(watchEntry); err != nil {
+		return err
+	}
+	if pathname == dir {
+		watchEntry.mask &= ^provisional
+	} else {
+		watchEntry.names[filepath.Base(pathname)] &= ^provisional
+	}
+	return nil
+}
+
+// Must run within the I/O thread.
+func (w *Watcher) remWatch(pathname string) error {
+	dir, err := getDir(pathname)
+	if err != nil {
+		return err
+	}
+	ino, err := getIno(dir)
+	if err != nil {
+		return err
+	}
+	w.mu.Lock()
+	watch := w.watches.get(ino)
+	w.mu.Unlock()
+	if watch == nil {
+		return fmt.Errorf("can't remove non-existent watch for: %s", pathname)
+	}
+	if pathname == dir {
+		w.sendEvent(watch.path, watch.mask&sysFSIGNORED)
+		watch.mask = 0
+	} else {
+		name := filepath.Base(pathname)
+		w.sendEvent(watch.path+"\\"+name, watch.names[name]&sysFSIGNORED)
+		delete(watch.names, name)
+	}
+	return w.startRead(watch)
+}
+
+// Must run within the I/O thread.
+func (w *Watcher) deleteWatch(watch *watch) {
+	for name, mask := range watch.names {
+		if mask&provisional == 0 {
+			w.sendEvent(watch.path+"\\"+name, mask&sysFSIGNORED)
+		}
+		delete(watch.names, name)
+	}
+	if watch.mask != 0 {
+		if watch.mask&provisional == 0 {
+			w.sendEvent(watch.path, watch.mask&sysFSIGNORED)
+		}
+		watch.mask = 0
+	}
+}
+
+// Must run within the I/O thread.
+func (w *Watcher) startRead(watch *watch) error {
+	if e := syscall.CancelIo(watch.ino.handle); e != nil {
+		w.Errors <- os.NewSyscallError("CancelIo", e)
+		w.deleteWatch(watch)
+	}
+	mask := toWindowsFlags(watch.mask)
+	for _, m := range watch.names {
+		mask |= toWindowsFlags(m)
+	}
+	if mask == 0 {
+		if e := syscall.CloseHandle(watch.ino.handle); e != nil {
+			w.Errors <- os.NewSyscallError("CloseHandle", e)
+		}
+		w.mu.Lock()
+		delete(w.watches[watch.ino.volume], watch.ino.index)
+		w.mu.Unlock()
+		return nil
+	}
+	e := syscall.ReadDirectoryChanges(watch.ino.handle, &watch.buf[0],
+		uint32(unsafe.Sizeof(watch.buf)), false, mask, nil, &watch.ov, 0)
+	if e != nil {
+		err := os.NewSyscallError("ReadDirectoryChanges", e)
+		if e == syscall.ERROR_ACCESS_DENIED && watch.mask&provisional == 0 {
+			// Watched directory was probably removed
+			if w.sendEvent(watch.path, watch.mask&sysFSDELETESELF) {
+				if watch.mask&sysFSONESHOT != 0 {
+					watch.mask = 0
+				}
+			}
+			err = nil
+		}
+		w.deleteWatch(watch)
+		w.startRead(watch)
+		return err
+	}
+	return nil
+}
+
+// readEvents reads from the I/O completion port, converts the
+// received events into Event objects and sends them via the Events channel.
+// Entry point to the I/O thread.
+func (w *Watcher) readEvents() {
+	var (
+		n, key uint32
+		ov     *syscall.Overlapped
+	)
+	runtime.LockOSThread()
+
+	for {
+		e := syscall.GetQueuedCompletionStatus(w.port, &n, &key, &ov, syscall.INFINITE)
+		watch := (*watch)(unsafe.Pointer(ov))
+
+		if watch == nil {
+			select {
+			case ch := <-w.quit:
+				w.mu.Lock()
+				var indexes []indexMap
+				for _, index := range w.watches {
+					indexes = append(indexes, index)
+				}
+				w.mu.Unlock()
+				for _, index := range indexes {
+					for _, watch := range index {
+						w.deleteWatch(watch)
+						w.startRead(watch)
+					}
+				}
+				var err error
+				if e := syscall.CloseHandle(w.port); e != nil {
+					err = os.NewSyscallError("CloseHandle", e)
+				}
+				close(w.Events)
+				close(w.Errors)
+				ch <- err
+				return
+			case in := <-w.input:
+				switch in.op {
+				case opAddWatch:
+					in.reply <- w.addWatch(in.path, uint64(in.flags))
+				case opRemoveWatch:
+					in.reply <- w.remWatch(in.path)
+				}
+			default:
+			}
+			continue
+		}
+
+		switch e {
+		case syscall.ERROR_MORE_DATA:
+			if watch == nil {
+				w.Errors <- errors.New("ERROR_MORE_DATA has unexpectedly null lpOverlapped buffer")
+			} else {
+				// The i/o succeeded but the buffer is full.
+				// In theory we should be building up a full packet.
+				// In practice we can get away with just carrying on.
+				n = uint32(unsafe.Sizeof(watch.buf))
+			}
+		case syscall.ERROR_ACCESS_DENIED:
+			// Watched directory was probably removed
+			w.sendEvent(watch.path, watch.mask&sysFSDELETESELF)
+			w.deleteWatch(watch)
+			w.startRead(watch)
+			continue
+		case syscall.ERROR_OPERATION_ABORTED:
+			// CancelIo was called on this handle
+			continue
+		default:
+			w.Errors <- os.NewSyscallError("GetQueuedCompletionPort", e)
+			continue
+		case nil:
+		}
+
+		var offset uint32
+		for {
+			if n == 0 {
+				w.Events <- newEvent("", sysFSQOVERFLOW)
+				w.Errors <- errors.New("short read in readEvents()")
+				break
+			}
+
+			// Point "raw" to the event in the buffer
+			raw := (*syscall.FileNotifyInformation)(unsafe.Pointer(&watch.buf[offset]))
+			buf := (*[syscall.MAX_PATH]uint16)(unsafe.Pointer(&raw.FileName))
+			name := syscall.UTF16ToString(buf[:raw.FileNameLength/2])
+			fullname := watch.path + "\\" + name
+
+			var mask uint64
+			switch raw.Action {
+			case syscall.FILE_ACTION_REMOVED:
+				mask = sysFSDELETESELF
+			case syscall.FILE_ACTION_MODIFIED:
+				mask = sysFSMODIFY
+			case syscall.FILE_ACTION_RENAMED_OLD_NAME:
+				watch.rename = name
+			case syscall.FILE_ACTION_RENAMED_NEW_NAME:
+				if watch.names[watch.rename] != 0 {
+					watch.names[name] |= watch.names[watch.rename]
+					delete(watch.names, watch.rename)
+					mask = sysFSMOVESELF
+				}
+			}
+
+			sendNameEvent := func() {
+				if w.sendEvent(fullname, watch.names[name]&mask) {
+					if watch.names[name]&sysFSONESHOT != 0 {
+						delete(watch.names, name)
+					}
+				}
+			}
+			if raw.Action != syscall.FILE_ACTION_RENAMED_NEW_NAME {
+				sendNameEvent()
+			}
+			if raw.Action == syscall.FILE_ACTION_REMOVED {
+				w.sendEvent(fullname, watch.names[name]&sysFSIGNORED)
+				delete(watch.names, name)
+			}
+			if w.sendEvent(fullname, watch.mask&toFSnotifyFlags(raw.Action)) {
+				if watch.mask&sysFSONESHOT != 0 {
+					watch.mask = 0
+				}
+			}
+			if raw.Action == syscall.FILE_ACTION_RENAMED_NEW_NAME {
+				fullname = watch.path + "\\" + watch.rename
+				sendNameEvent()
+			}
+
+			// Move to the next event in the buffer
+			if raw.NextEntryOffset == 0 {
+				break
+			}
+			offset += raw.NextEntryOffset
+
+			// Error!
+			if offset >= n {
+				w.Errors <- errors.New("Windows system assumed buffer larger than it is, events have likely been missed.")
+				break
+			}
+		}
+
+		if err := w.startRead(watch); err != nil {
+			w.Errors <- err
+		}
+	}
+}
+
+func (w *Watcher) sendEvent(name string, mask uint64) bool {
+	if mask == 0 {
+		return false
+	}
+	event := newEvent(name, uint32(mask))
+	select {
+	case ch := <-w.quit:
+		w.quit <- ch
+	case w.Events <- event:
+	}
+	return true
+}
+
+func toWindowsFlags(mask uint64) uint32 {
+	var m uint32
+	if mask&sysFSACCESS != 0 {
+		m |= syscall.FILE_NOTIFY_CHANGE_LAST_ACCESS
+	}
+	if mask&sysFSMODIFY != 0 {
+		m |= syscall.FILE_NOTIFY_CHANGE_LAST_WRITE
+	}
+	if mask&sysFSATTRIB != 0 {
+		m |= syscall.FILE_NOTIFY_CHANGE_ATTRIBUTES
+	}
+	if mask&(sysFSMOVE|sysFSCREATE|sysFSDELETE) != 0 {
+		m |= syscall.FILE_NOTIFY_CHANGE_FILE_NAME | syscall.FILE_NOTIFY_CHANGE_DIR_NAME
+	}
+	return m
+}
+
+func toFSnotifyFlags(action uint32) uint64 {
+	switch action {
+	case syscall.FILE_ACTION_ADDED:
+		return sysFSCREATE
+	case syscall.FILE_ACTION_REMOVED:
+		return sysFSDELETE
+	case syscall.FILE_ACTION_MODIFIED:
+		return sysFSMODIFY
+	case syscall.FILE_ACTION_RENAMED_OLD_NAME:
+		return sysFSMOVEDFROM
+	case syscall.FILE_ACTION_RENAMED_NEW_NAME:
+		return sysFSMOVEDTO
+	}
+	return 0
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/.gitignore b/vendor/gopkg.in/throttled/throttled.v1/.gitignore
new file mode 100644
index 000000000..c2a6499b4
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/.gitignore
@@ -0,0 +1,10 @@
+.DS_Store
+*.swp
+*.swo
+*.test
+examples/interval/interval
+examples/interval-vary/interval-vary
+examples/interval-many/interval-many
+examples/memstats/memstats
+examples/rate-limit/rate-limit
+examples/custom/custom
diff --git a/vendor/gopkg.in/throttled/throttled.v1/.travis.yml b/vendor/gopkg.in/throttled/throttled.v1/.travis.yml
new file mode 100644
index 000000000..1b2427202
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/.travis.yml
@@ -0,0 +1,10 @@
+sudo: false
+language: go
+
+go:
+    - 1.2
+    - tip
+
+install: go get -t ./...
+
+script: go test -v -short ./...
diff --git a/vendor/gopkg.in/throttled/throttled.v1/LICENSE b/vendor/gopkg.in/throttled/throttled.v1/LICENSE
new file mode 100644
index 000000000..f9616483e
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/LICENSE
@@ -0,0 +1,12 @@
+Copyright (c) 2014, Martin Angers and Contributors.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+
+* Neither the name of the author nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/gopkg.in/throttled/throttled.v1/README.md b/vendor/gopkg.in/throttled/throttled.v1/README.md
new file mode 100644
index 000000000..fbb4a01fc
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/README.md
@@ -0,0 +1,82 @@
+# Throttled [![build status](https://secure.travis-ci.org/throttled/throttled.png)](http://travis-ci.org/throttled/throttled) [![GoDoc](https://godoc.org/gopkg.in/throttled/throttled.v1?status.png)](http://godoc.org/gopkg.in/throttled/throttled.v1)
+
+Package throttled implements different throttling strategies for controlling
+access to HTTP handlers.
+
+*As of July 27, 2015, the package is now located under its own GitHub
+ organization and uses gopkg.in for versioning, please adjust your
+ imports to `gopkg.in/throttled/throttled.v1`.*
+
+## Installation
+
+`go get gopkg.in/throttled/throttled.v1/...`
+
+## Interval
+
+The Interval function creates a throttler that allows requests to go through at
+a controlled, constant interval. The interval may be applied to all requests
+(vary argument == nil) or independently based on vary-by criteria.
+
+For example:
+
+    th := throttled.Interval(throttled.PerSec(10), 100, &throttled.VaryBy{Path: true}, 50)
+    h := th.Throttle(myHandler)
+    http.ListenAndServe(":9000", h)
+
+Creates a throttler that will allow a request each 100ms (10 requests per second), with
+a buffer of 100 exceeding requests before dropping requests with a status code 429 (by
+default, configurable using th.DeniedHandler or the package-global DefaultDeniedHandler
+variable). Different paths will be throttled independently, so that /path_a and /path_b
+both can serve 10 requests per second. The last argument, 50, indicates the maximum number
+of keys that the throttler will keep in memory.
+
+## MemStats
+
+The MemStats function creates a throttler that allows requests to go through only if
+the memory statistics of the current process are below specified thresholds.
+
+For example:
+
+    th := throttled.MemStats(throttled.MemThresholds(&runtime.MemStats{NumGC: 10}, 10*time.Millisecond)
+    h := th.Throttle(myHandler)
+    http.ListenAndServe(":9000", h)
+
+Creates a throttler that will allow requests to go through until the number of garbage
+collections reaches the initial number + 10 (the MemThresholds function creates absolute
+memory stats thresholds from offsets). The second argument, 10ms, indicates the refresh
+rate of the memory stats.
+
+## RateLimit
+
+The RateLimit function creates a throttler that allows a certain number of requests in
+a given time window, as is often implemented in public RESTful APIs.
+
+For example:
+
+    th := throttled.RateLimit(throttled.PerMin(30), &throttled.VaryBy{RemoteAddr: true}, store.NewMemStore(1000))
+    h := th.Throttle(myHandler)
+    http.ListenAndServe(":9000", h)
+
+Creates a throttler that will limit requests to 30 per minute, based on the remote address
+of the client, and will store the counter and remaining time of the current window in the
+provided memory store, limiting the number of keys to keep in memory to 1000. The store
+sub-package also provides a Redis-based Store implementations.
+
+The RateLimit throttler sets the expected X-RateLimit-* headers on the response, and
+also sets a Retry-After header when the limit is exceeded.
+
+## Documentation
+
+The API documentation is available as usual on [godoc.org][doc].
+
+There is also a [blog post explaining the package's usage on 0value.com][blog].
+
+Finally, many examples are provided in the /examples sub-folder of the repository.
+
+## License
+
+The [BSD 3-clause license][bsd]. Copyright (c) 2014 Martin Angers and Contributors.
+
+[doc]: http://godoc.org/gopkg.in/throttled/throttled.v1
+[blog]: http://0value.com/throttled--guardian-of-the-web-server
+[bsd]: http://opensource.org/licenses/BSD-3-Clause
diff --git a/vendor/gopkg.in/throttled/throttled.v1/delayer.go b/vendor/gopkg.in/throttled/throttled.v1/delayer.go
new file mode 100644
index 000000000..e62ec9e86
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/delayer.go
@@ -0,0 +1,109 @@
+package throttled
+
+import "time"
+
+// The Quota interface defines the method to implement to describe
+// a time-window quota, as required by the RateLimit throttler.
+type Quota interface {
+	// Quota returns a number of requests allowed, and a duration.
+	Quota() (int, time.Duration)
+}
+
+// The Delayer interface defines the method to implement to describe
+// a delay as required by the Interval throttler.
+type Delayer interface {
+	// Delay returns a duration.
+	Delay() time.Duration
+}
+
+// PerSec represents a number of requests per second.
+type PerSec int
+
+// Delay returns the duration to wait before the next request can go through,
+// so that PerSec(n) == n requests per second at regular intervals.
+func (ps PerSec) Delay() time.Duration {
+	if ps <= 0 {
+		return 0
+	}
+	return time.Duration(1.0 / float64(ps) * float64(time.Second))
+}
+
+// Quota returns the number of requests allowed in a 1 second time window,
+// so that PerSec(n) == n requests allowed per second.
+func (ps PerSec) Quota() (int, time.Duration) {
+	return int(ps), time.Second
+}
+
+// PerMin represents a number of requests per minute.
+type PerMin int
+
+// Delay returns the duration to wait before the next request can go through,
+// so that PerMin(n) == n requests per minute at regular intervals.
+func (pm PerMin) Delay() time.Duration {
+	if pm <= 0 {
+		return 0
+	}
+	return time.Duration(1.0 / float64(pm) * float64(time.Minute))
+}
+
+// Quota returns the number of requests allowed in a 1 minute time window,
+// so that PerMin(n) == n requests allowed per minute.
+func (pm PerMin) Quota() (int, time.Duration) {
+	return int(pm), time.Minute
+}
+
+// PerHour represents a number of requests per hour.
+type PerHour int
+
+// Delay returns the duration to wait before the next request can go through,
+// so that PerHour(n) == n requests per hour at regular intervals.
+func (ph PerHour) Delay() time.Duration {
+	if ph <= 0 {
+		return 0
+	}
+	return time.Duration(1.0 / float64(ph) * float64(time.Hour))
+}
+
+// Quota returns the number of requests allowed in a 1 hour time window,
+// so that PerHour(n) == n requests allowed per hour.
+func (ph PerHour) Quota() (int, time.Duration) {
+	return int(ph), time.Hour
+}
+
+// PerDay represents a number of requests per day.
+type PerDay int
+
+// Delay returns the duration to wait before the next request can go through,
+// so that PerDay(n) == n requests per day at regular intervals.
+func (pd PerDay) Delay() time.Duration {
+	if pd <= 0 {
+		return 0
+	}
+	return time.Duration(1.0 / float64(pd) * float64(24*time.Hour))
+}
+
+// Quota returns the number of requests allowed in a 1 day time window,
+// so that PerDay(n) == n requests allowed per day.
+func (pd PerDay) Quota() (int, time.Duration) {
+	return int(pd), 24 * time.Hour
+}
+
+// D represents a custom delay.
+type D time.Duration
+
+// Delay returns the duration to wait before the next request can go through,
+// which is the custom duration represented by the D value.
+func (d D) Delay() time.Duration {
+	return time.Duration(d)
+}
+
+// Q represents a custom quota.
+type Q struct {
+	Requests int
+	Window   time.Duration
+}
+
+// Quota returns the number of requests allowed and the custom time window.
+func (q Q) Quota() (int, time.Duration) {
+	return q.Requests, q.Window
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/doc.go b/vendor/gopkg.in/throttled/throttled.v1/doc.go
new file mode 100644
index 000000000..acf5213b0
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/doc.go
@@ -0,0 +1,77 @@
+// Package throttled implements different throttling strategies for controlling
+// access to HTTP handlers.
+//
+// Installation
+//
+// go get gopkg.in/throttled/throttled.v1/...
+//
+// Inverval
+//
+// The Interval function creates a throttler that allows requests to go through at
+// a controlled, constant interval. The interval may be applied to all requests
+// (vary argument == nil) or independently based on vary-by criteria.
+//
+// For example:
+//
+//    th := throttled.Interval(throttled.PerSec(10), 100, &throttled.VaryBy{Path: true}, 50)
+//    h := th.Throttle(myHandler)
+//    http.ListenAndServe(":9000", h)
+//
+// Creates a throttler that will allow a request each 100ms (10 requests per second), with
+// a buffer of 100 exceeding requests before dropping requests with a status code 429 (by
+// default, configurable using th.DeniedHandler or the package-global DefaultDeniedHandler
+// variable). Different paths will be throttled independently, so that /path_a and /path_b
+// both can serve 10 requests per second. The last argument, 50, indicates the maximum number
+// of keys that the throttler will keep in memory.
+//
+// MemStats
+//
+// The MemStats function creates a throttler that allows requests to go through only if
+// the memory statistics of the current process are below specified thresholds.
+//
+// For example:
+//
+//    th := throttled.MemStats(throttled.MemThresholds(&runtime.MemStats{NumGC: 10}, 10*time.Millisecond)
+//    h := th.Throttle(myHandler)
+//    http.ListenAndServe(":9000", h)
+//
+// Creates a throttler that will allow requests to go through until the number of garbage
+// collections reaches the initial number + 10 (the MemThresholds function creates absolute
+// memory stats thresholds from offsets). The second argument, 10ms, indicates the refresh
+// rate of the memory stats.
+//
+// RateLimit
+//
+// The RateLimit function creates a throttler that allows a certain number of requests in
+// a given time window, as is often implemented in public RESTful APIs.
+//
+// For example:
+//
+//    th := throttled.RateLimit(throttled.PerMin(30), &throttled.VaryBy{RemoteAddr: true}, store.NewMemStore(1000))
+//    h := th.Throttle(myHandler)
+//    http.ListenAndServe(":9000", h)
+//
+// Creates a throttler that will limit requests to 30 per minute, based on the remote address
+// of the client, and will store the counter and remaining time of the current window in the
+// provided memory store, limiting the number of keys to keep in memory to 1000. The store
+// sub-package also provides a Redis-based Store implementations.
+//
+// The RateLimit throttler sets the expected X-RateLimit-* headers on the response, and
+// also sets a Retry-After header when the limit is exceeded.
+//
+// Documentation
+//
+// The API documentation is available as usual on godoc.org:
+//    http://godoc.org/gopkg.in/throttled/throttled.v1
+//
+// There is also a blog post explaining the package's usage on 0value.com:
+//    http://0value.com/throttled--guardian-of-the-web-server
+//
+// Finally, many examples are provided in the /examples sub-folder of the repository.
+//
+// License
+//
+// The BSD 3-clause license. Copyright (c) 2014 Martin Angers and Contributors.
+//    http://opensource.org/licenses/BSD-3-Clause
+//
+package throttled
diff --git a/vendor/gopkg.in/throttled/throttled.v1/interval.go b/vendor/gopkg.in/throttled/throttled.v1/interval.go
new file mode 100644
index 000000000..628a5593e
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/interval.go
@@ -0,0 +1,164 @@
+package throttled
+
+import (
+	"net/http"
+	"sync"
+	"time"
+
+	"github.com/golang/groupcache/lru"
+)
+
+// Static check to ensure that the interval limiters implement the Limiter interface.
+var _ Limiter = (*intervalVaryByLimiter)(nil)
+var _ Limiter = (*intervalLimiter)(nil)
+
+// Interval creates a throttler that controls the requests so that they
+// go through at a constant interval. The interval is specified by the
+// delay argument, and convenience types such as PerSec can be used to
+// express the interval in a more expressive way, i.e. PerSec(10) means
+// 10 requests per second or one request each 100ms, PerMin(30) means
+// 30 requests per minute or on request each 2s, etc.
+//
+// The bursts argument indicates the number of exceeding requests that may
+// be queued up waiting to be processed. Requests that overflow the queue
+// are dropped and go through the denied handler, which may be specified
+// on the Throttler and that defaults to the package-global variable
+// DefaultDeniedHandler.
+//
+// The vary argument indicates the criteria to use to group the requests,
+// so that the interval applies to the requests in the same group (e.g. based on
+// the path, or the remote IP address, etc.). If this argument is nil, the
+// interval applies to all requests going through this throttler.
+//
+// The maxKeys indicates the maximum number of keys to keep in memory to apply the interval,
+// when a vary argument is specified. A LRU algorithm is used to remove older keys.
+//
+func Interval(delay Delayer, bursts int, vary *VaryBy, maxKeys int) *Throttler {
+	var l Limiter
+	if vary != nil {
+		if maxKeys < 1 {
+			maxKeys = 1
+		}
+		l = &intervalVaryByLimiter{
+			delay:   delay.Delay(),
+			bursts:  bursts,
+			vary:    vary,
+			maxKeys: maxKeys,
+		}
+	} else {
+		l = &intervalLimiter{
+			delay:  delay.Delay(),
+			bursts: bursts,
+		}
+	}
+	return &Throttler{
+		limiter: l,
+	}
+}
+
+// The intervalLimiter struct implements an interval limiter with no vary-by
+// criteria.
+type intervalLimiter struct {
+	delay  time.Duration
+	bursts int
+
+	bucket chan chan bool
+}
+
+// Start initializes the limiter for execution.
+func (il *intervalLimiter) Start() {
+	if il.bursts < 0 {
+		il.bursts = 0
+	}
+	il.bucket = make(chan chan bool, il.bursts)
+	go process(il.bucket, il.delay)
+}
+
+// Limit is called for each request to the throttled handler. It tries to
+// queue the request to allow it to run at the given interval, but if the
+// queue is full, the request is denied access.
+func (il *intervalLimiter) Limit(w http.ResponseWriter, r *http.Request) (<-chan bool, error) {
+	ch := make(chan bool, 1)
+	select {
+	case il.bucket <- ch:
+		return ch, nil
+	default:
+		ch <- false
+		return ch, nil
+	}
+}
+
+// The intervalVaryByLimiter struct implements an interval limiter with a vary-by
+// criteria.
+type intervalVaryByLimiter struct {
+	delay  time.Duration
+	bursts int
+	vary   *VaryBy
+
+	lock    sync.RWMutex
+	keys    *lru.Cache
+	maxKeys int
+}
+
+// Start initializes the limiter for execution.
+func (il *intervalVaryByLimiter) Start() {
+	if il.bursts < 0 {
+		il.bursts = 0
+	}
+	il.keys = lru.New(il.maxKeys)
+	il.keys.OnEvicted = il.stopProcess
+}
+
+// Limit is called for each request to the throttled handler. It tries to
+// queue the request for the vary-by key to allow it to run at the given interval,
+// but if the queue is full, the request is denied access.
+func (il *intervalVaryByLimiter) Limit(w http.ResponseWriter, r *http.Request) (<-chan bool, error) {
+	ch := make(chan bool, 1)
+	key := il.vary.Key(r)
+
+	il.lock.RLock()
+	item, ok := il.keys.Get(key)
+	if !ok {
+		// Create the key, bucket, start goroutine
+		// First release the read lock and acquire a write lock
+		il.lock.RUnlock()
+		il.lock.Lock()
+		// Create the bucket, add the key
+		bucket := make(chan chan bool, il.bursts)
+		il.keys.Add(key, bucket)
+		// Start the goroutine to process this bucket
+		go process(bucket, il.delay)
+		item = bucket
+		// Release the write lock, acquire the read lock
+		il.lock.Unlock()
+		il.lock.RLock()
+	}
+	defer il.lock.RUnlock()
+	bucket := item.(chan chan bool)
+	select {
+	case bucket <- ch:
+		return ch, nil
+	default:
+		ch <- false
+		return ch, nil
+	}
+}
+
+// process loops through the queued requests for a key's bucket, and sends
+// requests through at the given interval.
+func process(bucket chan chan bool, delay time.Duration) {
+	after := time.After(0)
+	for v := range bucket {
+		<-after
+		// Let the request go through
+		v <- true
+		// Wait the required duration
+		after = time.After(delay)
+	}
+}
+
+// stopProcess is called when a key is removed from the LRU cache so that its
+// accompanying goroutine is correctly released.
+func (il *intervalVaryByLimiter) stopProcess(key lru.Key, value interface{}) {
+	close(value.(chan chan bool))
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/memstats.go b/vendor/gopkg.in/throttled/throttled.v1/memstats.go
new file mode 100644
index 000000000..bd2765630
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/memstats.go
@@ -0,0 +1,214 @@
+package throttled
+
+import (
+	"net/http"
+	"runtime"
+	"sync"
+	"time"
+)
+
+// Static check to ensure that memStatsLimiter implements Limiter.
+var _ Limiter = (*memStatsLimiter)(nil)
+
+// The memStatsLimiter struct implements a limiter based on the memory statistics
+// of the current process.
+type memStatsLimiter struct {
+	thresholds  *runtime.MemStats
+	refreshRate time.Duration
+
+	lockStats sync.RWMutex
+	stats     runtime.MemStats
+}
+
+// MemStats creates a Throttler based on the memory statistics of the current process.
+// Any combination of any (non-array) integer field of Go's runtime.MemStats structure
+// can be used as thresholds to deny a request.
+//
+// As soon as one threshold value is reached, the access is denied. If the value can
+// decrease, access will be allowed again once it gets back under the threshold value.
+// Denied requests go through the denied handler, which may be specified on the Throttler
+// and that defaults to the package-global variable DefaultDeniedHandler.
+//
+// Thresholds must be specified in absolute numbers (i.e. NumGC = 10 means stop once the
+// NumGC reaches 10, not when the current value increments by 10), and zero values are
+// ignored.
+//
+// The refreshRate indicates the frequency at which the process' memory stats are refreshed,
+// and 0 means on each request.
+//
+func MemStats(thresholds *runtime.MemStats, refreshRate time.Duration) *Throttler {
+	return &Throttler{
+		limiter: &memStatsLimiter{
+			thresholds:  thresholds,
+			refreshRate: refreshRate,
+		},
+	}
+}
+
+// Start initialized the limiter for execution.
+func (m *memStatsLimiter) Start() {
+	// Make sure there is an initial MemStats reading
+	runtime.ReadMemStats(&m.stats)
+	if m.refreshRate > 0 {
+		go m.refresh()
+	}
+}
+
+// refresh runs in a separate goroutine and refreshes the memory statistics
+// at regular intervals.
+func (m *memStatsLimiter) refresh() {
+	c := time.Tick(m.refreshRate)
+	for _ = range c {
+		m.lockStats.Lock()
+		runtime.ReadMemStats(&m.stats)
+		m.lockStats.Unlock()
+	}
+}
+
+// Limit is called for each request to the throttled handler. It checks if
+// the request can go through by checking the memory thresholds, and signals it
+// via the returned channel.
+func (m *memStatsLimiter) Limit(w http.ResponseWriter, r *http.Request) (<-chan bool, error) {
+	ch := make(chan bool, 1)
+	// Check if memory thresholds are reached
+	ch <- m.allow()
+	return ch, nil
+}
+
+// allow compares the current memory stats with the thresholds, and returns
+// false if any threshold is reached.
+func (m *memStatsLimiter) allow() bool {
+	m.lockStats.RLock()
+	mem := m.stats
+	m.lockStats.RUnlock()
+	// If refreshRate == 0, then read on every request.
+	if m.refreshRate == 0 {
+		runtime.ReadMemStats(&mem)
+	}
+	ok := true
+	checkStat(m.thresholds.Alloc, mem.Alloc, &ok)
+	checkStat(m.thresholds.BuckHashSys, mem.BuckHashSys, &ok)
+	checkStat(m.thresholds.Frees, mem.Frees, &ok)
+	checkStat(m.thresholds.GCSys, mem.GCSys, &ok)
+	checkStat(m.thresholds.HeapAlloc, mem.HeapAlloc, &ok)
+	checkStat(m.thresholds.HeapIdle, mem.HeapIdle, &ok)
+	checkStat(m.thresholds.HeapInuse, mem.HeapInuse, &ok)
+	checkStat(m.thresholds.HeapObjects, mem.HeapObjects, &ok)
+	checkStat(m.thresholds.HeapReleased, mem.HeapReleased, &ok)
+	checkStat(m.thresholds.HeapSys, mem.HeapSys, &ok)
+	checkStat(m.thresholds.LastGC, mem.LastGC, &ok)
+	checkStat(m.thresholds.Lookups, mem.Lookups, &ok)
+	checkStat(m.thresholds.MCacheInuse, mem.MCacheInuse, &ok)
+	checkStat(m.thresholds.MCacheSys, mem.MCacheSys, &ok)
+	checkStat(m.thresholds.MSpanInuse, mem.MSpanInuse, &ok)
+	checkStat(m.thresholds.MSpanSys, mem.MSpanSys, &ok)
+	checkStat(m.thresholds.Mallocs, mem.Mallocs, &ok)
+	checkStat(m.thresholds.NextGC, mem.NextGC, &ok)
+	checkStat(uint64(m.thresholds.NumGC), uint64(mem.NumGC), &ok)
+	checkStat(m.thresholds.OtherSys, mem.OtherSys, &ok)
+	checkStat(m.thresholds.PauseTotalNs, mem.PauseTotalNs, &ok)
+	checkStat(m.thresholds.StackInuse, mem.StackInuse, &ok)
+	checkStat(m.thresholds.StackSys, mem.StackSys, &ok)
+	checkStat(m.thresholds.Sys, mem.Sys, &ok)
+	checkStat(m.thresholds.TotalAlloc, mem.TotalAlloc, &ok)
+	return ok
+}
+
+// Checks the threshold value against the actual value, and assigns false
+// to the boolean pointer if the threshold is reached.
+func checkStat(threshold, actual uint64, ok *bool) {
+	if !*ok {
+		return
+	}
+	if threshold > 0 {
+		if actual >= threshold {
+			*ok = false
+		}
+	}
+}
+
+// MemThresholds is a convenience function to create a thresholds memory stats from
+// offsets to apply to the current memory stats. Zero values in the offset stats
+// are left to 0 in the resulting thresholds memory stats value.
+//
+// The return value may be used as thresholds argument to the MemStats function.
+func MemThresholds(offset *runtime.MemStats) *runtime.MemStats {
+	var mem, thr runtime.MemStats
+	runtime.ReadMemStats(&mem)
+	if offset.Alloc > 0 {
+		thr.Alloc = mem.Alloc + offset.Alloc
+	}
+	if offset.BuckHashSys > 0 {
+		thr.BuckHashSys = mem.BuckHashSys + offset.BuckHashSys
+	}
+	if offset.Frees > 0 {
+		thr.Frees = mem.Frees + offset.Frees
+	}
+	if offset.GCSys > 0 {
+		thr.GCSys = mem.GCSys + offset.GCSys
+	}
+	if offset.HeapAlloc > 0 {
+		thr.HeapAlloc = mem.HeapAlloc + offset.HeapAlloc
+	}
+	if offset.HeapIdle > 0 {
+		thr.HeapIdle = mem.HeapIdle + offset.HeapIdle
+	}
+	if offset.HeapInuse > 0 {
+		thr.HeapInuse = mem.HeapInuse + offset.HeapInuse
+	}
+	if offset.HeapObjects > 0 {
+		thr.HeapObjects = mem.HeapObjects + offset.HeapObjects
+	}
+	if offset.HeapReleased > 0 {
+		thr.HeapReleased = mem.HeapReleased + offset.HeapReleased
+	}
+	if offset.HeapSys > 0 {
+		thr.HeapSys = mem.HeapSys + offset.HeapSys
+	}
+	if offset.LastGC > 0 {
+		thr.LastGC = mem.LastGC + offset.LastGC
+	}
+	if offset.Lookups > 0 {
+		thr.Lookups = mem.Lookups + offset.Lookups
+	}
+	if offset.MCacheInuse > 0 {
+		thr.MCacheInuse = mem.MCacheInuse + offset.MCacheInuse
+	}
+	if offset.MCacheSys > 0 {
+		thr.MCacheSys = mem.MCacheSys + offset.MCacheSys
+	}
+	if offset.MSpanInuse > 0 {
+		thr.MSpanInuse = mem.MSpanInuse + offset.MSpanInuse
+	}
+	if offset.MSpanSys > 0 {
+		thr.MSpanSys = mem.MSpanSys + offset.MSpanSys
+	}
+	if offset.Mallocs > 0 {
+		thr.Mallocs = mem.Mallocs + offset.Mallocs
+	}
+	if offset.NextGC > 0 {
+		thr.NextGC = mem.NextGC + offset.NextGC
+	}
+	if offset.NumGC > 0 {
+		thr.NumGC = mem.NumGC + offset.NumGC
+	}
+	if offset.OtherSys > 0 {
+		thr.OtherSys = mem.OtherSys + offset.OtherSys
+	}
+	if offset.PauseTotalNs > 0 {
+		thr.PauseTotalNs = mem.PauseTotalNs + offset.PauseTotalNs
+	}
+	if offset.StackInuse > 0 {
+		thr.StackInuse = mem.StackInuse + offset.StackInuse
+	}
+	if offset.StackSys > 0 {
+		thr.StackSys = mem.StackSys + offset.StackSys
+	}
+	if offset.Sys > 0 {
+		thr.Sys = mem.Sys + offset.Sys
+	}
+	if offset.TotalAlloc > 0 {
+		thr.TotalAlloc = mem.TotalAlloc + offset.TotalAlloc
+	}
+	return &thr
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/rate.go b/vendor/gopkg.in/throttled/throttled.v1/rate.go
new file mode 100644
index 000000000..d7a7de6d7
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/rate.go
@@ -0,0 +1,116 @@
+package throttled
+
+import (
+	"math"
+	"net/http"
+	"strconv"
+	"time"
+)
+
+// Static check to ensure that rateLimiter implements Limiter.
+var _ Limiter = (*rateLimiter)(nil)
+
+// RateLimit creates a throttler that limits the number of requests allowed
+// in a certain time window defined by the Quota q. The q parameter specifies
+// the requests per time window, and it is silently set to at least 1 request
+// and at least a 1 second window if it is less than that. The time window
+// starts when the first request is made outside an existing window. Fractions
+// of seconds are not supported, they are truncated.
+//
+// The vary parameter indicates what criteria should be used to group requests
+// for which the limit must be applied (ex.: rate limit based on the remote address).
+// See varyby.go for the various options.
+//
+// The specified store is used to keep track of the request count and the
+// time remaining in the window. The throttled package comes with some stores
+// in the throttled/store package. Custom stores can be created too, by implementing
+// the Store interface.
+//
+// Requests that bust the rate limit are denied access and go through the denied handler,
+// which may be specified on the Throttler and that defaults to the package-global
+// variable DefaultDeniedHandler.
+//
+// The rate limit throttler sets the following headers on the response:
+//
+//    X-RateLimit-Limit : quota
+//    X-RateLimit-Remaining : number of requests remaining in the current window
+//    X-RateLimit-Reset : seconds before a new window
+//
+// Additionally, if the request was denied access, the following header is added:
+//
+//    Retry-After : seconds before the caller should retry
+//
+func RateLimit(q Quota, vary *VaryBy, store Store) *Throttler {
+	// Extract requests and window
+	reqs, win := q.Quota()
+
+	// Create and return the throttler
+	return &Throttler{
+		limiter: &rateLimiter{
+			reqs:   reqs,
+			window: win,
+			vary:   vary,
+			store:  store,
+		},
+	}
+}
+
+// The rate limiter implements limiting the request to a certain quota
+// based on the vary-by criteria. State is saved in the store.
+type rateLimiter struct {
+	reqs   int
+	window time.Duration
+	vary   *VaryBy
+	store  Store
+}
+
+// Start initializes the limiter for execution.
+func (r *rateLimiter) Start() {
+	if r.reqs < 1 {
+		r.reqs = 1
+	}
+	if r.window < time.Second {
+		r.window = time.Second
+	}
+}
+
+// Limit is called for each request to the throttled handler. It checks if
+// the request can go through and signals it via the returned channel.
+// It returns an error if the operation fails.
+func (r *rateLimiter) Limit(w http.ResponseWriter, req *http.Request) (<-chan bool, error) {
+	// Create return channel and initialize
+	ch := make(chan bool, 1)
+	ok := true
+	key := r.vary.Key(req)
+
+	// Get the current count and remaining seconds
+	cnt, secs, err := r.store.Incr(key, r.window)
+	// Handle the possible situations: error, begin new window, or increment current window.
+	switch {
+	case err != nil && err != ErrNoSuchKey:
+		// An unexpected error occurred
+		return nil, err
+	case err == ErrNoSuchKey || secs <= 0:
+		// Reset counter
+		if err := r.store.Reset(key, r.window); err != nil {
+			return nil, err
+		}
+		cnt = 1
+		secs = int(r.window.Seconds())
+	default:
+		// If the limit is reached, deny access
+		if cnt > r.reqs {
+			ok = false
+		}
+	}
+	// Set rate-limit headers
+	w.Header().Add("X-RateLimit-Limit", strconv.Itoa(r.reqs))
+	w.Header().Add("X-RateLimit-Remaining", strconv.Itoa(int(math.Max(float64(r.reqs-cnt), 0))))
+	w.Header().Add("X-RateLimit-Reset", strconv.Itoa(secs))
+	if !ok {
+		w.Header().Add("Retry-After", strconv.Itoa(secs))
+	}
+	// Send response via the return channel
+	ch <- ok
+	return ch, nil
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/store.go b/vendor/gopkg.in/throttled/throttled.v1/store.go
new file mode 100644
index 000000000..760fe2b69
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/store.go
@@ -0,0 +1,31 @@
+package throttled
+
+import (
+	"errors"
+	"time"
+)
+
+// The error returned if the key does not exist in the Store.
+var ErrNoSuchKey = errors.New("throttled: no such key")
+
+// Store is the interface to implement to store the RateLimit state (number
+// of requests per key, time-to-live or creation timestamp).
+type Store interface {
+	// Incr increments the count for the specified key and returns the new value along
+	// with the number of seconds remaining. It may return an error
+	// if the operation fails.
+	//
+	// The method may return ErrNoSuchKey if the key to increment does not exist,
+	// in which case Reset will be called to initialize the value.
+	Incr(string, time.Duration) (int, int, error)
+
+	// Reset resets the key to 1 with the specified window duration. It must create the
+	// key if it doesn't exist. It returns an error if it fails.
+	Reset(string, time.Duration) error
+}
+
+// RemainingSeconds is a helper function that returns the number of seconds
+// remaining from an absolute timestamp in UTC.
+func RemainingSeconds(ts time.Time, window time.Duration) int {
+	return int((window - time.Now().UTC().Sub(ts)).Seconds())
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/store/doc.go b/vendor/gopkg.in/throttled/throttled.v1/store/doc.go
new file mode 100644
index 000000000..adb4618d3
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/store/doc.go
@@ -0,0 +1,2 @@
+// Package store offers a memory-based and a Redis-based throttled.Store implementation.
+package store
diff --git a/vendor/gopkg.in/throttled/throttled.v1/store/mem.go b/vendor/gopkg.in/throttled/throttled.v1/store/mem.go
new file mode 100644
index 000000000..22d200e8d
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/store/mem.go
@@ -0,0 +1,90 @@
+package store
+
+import (
+	"sync"
+	"time"
+
+	"github.com/golang/groupcache/lru"
+	"gopkg.in/throttled/throttled.v1"
+)
+
+// memStore implements an in-memory Store.
+type memStore struct {
+	sync.Mutex
+	keys *lru.Cache
+	m    map[string]*counter
+}
+
+// NewMemStore creates a new MemStore. If maxKeys > 0, the number of different keys
+// is restricted to the specified amount. In this case, it uses an LRU algorithm to
+// evict older keys to make room for newer ones. If a request is made for a key that
+// has been evicted, it will be processed as if its count was 0, possibly allowing requests
+// that should be denied.
+//
+// If maxKeys <= 0, there is no limit on the number of keys, which may use an unbounded amount of
+// memory depending on the server's load.
+//
+// The MemStore is only for single-process rate-limiting. To share the rate limit state
+// among multiple instances of the web server, use a database- or key-value-based
+// store.
+//
+func NewMemStore(maxKeys int) throttled.Store {
+	var m *memStore
+	if maxKeys > 0 {
+		m = &memStore{
+			keys: lru.New(maxKeys),
+		}
+	} else {
+		m = &memStore{
+			m: make(map[string]*counter),
+		}
+	}
+	return m
+}
+
+// A counter represents a single entry in the MemStore.
+type counter struct {
+	n  int
+	ts time.Time
+}
+
+// Incr increments the counter for the specified key. It returns the new
+// count value and the remaining number of seconds, or an error.
+func (ms *memStore) Incr(key string, window time.Duration) (int, int, error) {
+	ms.Lock()
+	defer ms.Unlock()
+	var c *counter
+	if ms.keys != nil {
+		v, _ := ms.keys.Get(key)
+		if v != nil {
+			c = v.(*counter)
+		}
+	} else {
+		c = ms.m[key]
+	}
+	if c == nil {
+		c = &counter{0, time.Now().UTC()}
+	}
+	c.n++
+	if ms.keys != nil {
+		ms.keys.Add(key, c)
+	} else {
+		ms.m[key] = c
+	}
+	return c.n, throttled.RemainingSeconds(c.ts, window), nil
+}
+
+// Reset resets the counter for the specified key. It sets the count
+// to 1 and initializes the timestamp with the current time, in UTC.
+// It returns an error if the operation fails.
+func (ms *memStore) Reset(key string, win time.Duration) error {
+	ms.Lock()
+	defer ms.Unlock()
+	c := &counter{1, time.Now().UTC()}
+	if ms.keys != nil {
+		ms.keys.Add(key, c)
+	} else {
+		ms.m[key] = c
+	}
+	return nil
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/store/redis.go b/vendor/gopkg.in/throttled/throttled.v1/store/redis.go
new file mode 100644
index 000000000..b089f9f4e
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/store/redis.go
@@ -0,0 +1,85 @@
+package store
+
+import (
+	"time"
+
+	"github.com/garyburd/redigo/redis"
+	"gopkg.in/throttled/throttled.v1"
+)
+
+// redisStore implements a Redis-based store.
+type redisStore struct {
+	pool   *redis.Pool
+	prefix string
+	db     int
+}
+
+// NewRedisStore creates a new Redis-based store, using the provided pool to get its
+// connections. The keys will have the specified keyPrefix, which may be an empty string,
+// and the database index specified by db will be selected to store the keys.
+//
+func NewRedisStore(pool *redis.Pool, keyPrefix string, db int) throttled.Store {
+	return &redisStore{
+		pool:   pool,
+		prefix: keyPrefix,
+		db:     db,
+	}
+}
+
+// Incr increments the specified key. If the key did not exist, it sets it to 1
+// and sets it to expire after the number of seconds specified by window.
+//
+// It returns the new count value and the number of remaining seconds, or an error
+// if the operation fails.
+func (r *redisStore) Incr(key string, window time.Duration) (int, int, error) {
+	conn := r.pool.Get()
+	defer conn.Close()
+	if err := selectDB(r.db, conn); err != nil {
+		return 0, 0, err
+	}
+	// Atomically increment and read the TTL.
+	conn.Send("MULTI")
+	conn.Send("INCR", r.prefix+key)
+	conn.Send("TTL", r.prefix+key)
+	vals, err := redis.Values(conn.Do("EXEC"))
+	if err != nil {
+		conn.Do("DISCARD")
+		return 0, 0, err
+	}
+	var cnt, ttl int
+	if _, err = redis.Scan(vals, &cnt, &ttl); err != nil {
+		return 0, 0, err
+	}
+	// If there was no TTL set, then this is a newly created key (INCR creates the key
+	// if it didn't exist), so set it to expire.
+	if ttl == -1 {
+		ttl = int(window.Seconds())
+		_, err = conn.Do("EXPIRE", r.prefix+key, ttl)
+		if err != nil {
+			return 0, 0, err
+		}
+	}
+	return cnt, ttl, nil
+}
+
+// Reset sets the value of the key to 1, and resets its time window.
+func (r *redisStore) Reset(key string, window time.Duration) error {
+	conn := r.pool.Get()
+	defer conn.Close()
+	if err := selectDB(r.db, conn); err != nil {
+		return err
+	}
+	_, err := redis.String(conn.Do("SET", r.prefix+key, "1", "EX", int(window.Seconds()), "NX"))
+	return err
+}
+
+// Select the specified database index.
+func selectDB(db int, conn redis.Conn) error {
+	// Select the specified database
+	if db > 0 {
+		if _, err := redis.String(conn.Do("SELECT", db)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/throttler.go b/vendor/gopkg.in/throttled/throttled.v1/throttler.go
new file mode 100644
index 000000000..06da13051
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/throttler.go
@@ -0,0 +1,86 @@
+package throttled
+
+import (
+	"net/http"
+	"sync"
+)
+
+var (
+	// DefaultDeniedHandler handles the requests that were denied access because
+	// of a throttler. By default, returns a 429 status code with a
+	// generic message.
+	DefaultDeniedHandler = http.Handler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Error(w, "limit exceeded", 429)
+	}))
+
+	// Error is the function to call when an error occurs on a throttled handler.
+	// By default, returns a 500 status code with a generic message.
+	Error = ErrorFunc(func(w http.ResponseWriter, r *http.Request, err error) {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+	})
+)
+
+// ErrorFunc defines the function type for the Error variable.
+type ErrorFunc func(w http.ResponseWriter, r *http.Request, err error)
+
+// The Limiter interface defines the methods required to control access to a
+// throttled handler.
+type Limiter interface {
+	Start()
+	Limit(http.ResponseWriter, *http.Request) (<-chan bool, error)
+}
+
+// Custom creates a Throttler using the provided Limiter implementation.
+func Custom(l Limiter) *Throttler {
+	return &Throttler{
+		limiter: l,
+	}
+}
+
+// A Throttler controls access to HTTP handlers using a Limiter.
+type Throttler struct {
+	// DeniedHandler is called if the request is disallowed. If it is nil,
+	// the DefaultDeniedHandler variable is used.
+	DeniedHandler http.Handler
+
+	limiter Limiter
+	// The mutex protects the started flag
+	mu      sync.Mutex
+	started bool
+}
+
+// Throttle wraps a HTTP handler so that its access is controlled by
+// the Throttler. It returns the Handler with the throttling logic.
+func (t *Throttler) Throttle(h http.Handler) http.Handler {
+	dh := t.start()
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ch, err := t.limiter.Limit(w, r)
+		if err != nil {
+			Error(w, r, err)
+			return
+		}
+		ok := <-ch
+		if ok {
+			h.ServeHTTP(w, r)
+		} else {
+			dh.ServeHTTP(w, r)
+		}
+	})
+}
+
+// start starts the throttling and returns the effective denied handler to
+// use for requests that were denied access.
+func (t *Throttler) start() http.Handler {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	// Get the effective denied handler
+	dh := t.DeniedHandler
+	if dh == nil {
+		dh = DefaultDeniedHandler
+	}
+	if !t.started {
+		t.limiter.Start()
+		t.started = true
+	}
+	return dh
+}
diff --git a/vendor/gopkg.in/throttled/throttled.v1/varyby.go b/vendor/gopkg.in/throttled/throttled.v1/varyby.go
new file mode 100644
index 000000000..3b2cdb011
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/varyby.go
@@ -0,0 +1,78 @@
+package throttled
+
+import (
+	"bytes"
+	"net/http"
+	"strings"
+)
+
+// VaryBy defines the criteria to use to group requests.
+type VaryBy struct {
+	// Vary by the RemoteAddr as specified by the net/http.Request field.
+	RemoteAddr bool
+
+	// Vary by the HTTP Method as specified by the net/http.Request field.
+	Method bool
+
+	// Vary by the URL's Path as specified by the Path field of the net/http.Request
+	// URL field.
+	Path bool
+
+	// Vary by this list of header names, read from the net/http.Request Header field.
+	Headers []string
+
+	// Vary by this list of parameters, read from the net/http.Request FormValue method.
+	Params []string
+
+	// Vary by this list of cookie names, read from the net/http.Request Cookie method.
+	Cookies []string
+
+	// Use this separator string to concatenate the various criteria of the VaryBy struct.
+	// Defaults to a newline character if empty (\n).
+	Separator string
+
+	// Custom specifies the custom-generated key to use for this request.
+	// If not nil, the value returned by this function is used instead of any
+	// VaryBy criteria.
+	Custom func(r *http.Request) string
+}
+
+// Key returns the key for this request based on the criteria defined by the VaryBy struct.
+func (vb *VaryBy) Key(r *http.Request) string {
+	var buf bytes.Buffer
+
+	if vb == nil {
+		return "" // Special case for no vary-by option
+	}
+	if vb.Custom != nil {
+		// A custom key generator is specified
+		return vb.Custom(r)
+	}
+	sep := vb.Separator
+	if sep == "" {
+		sep = "\n" // Separator defaults to newline
+	}
+	if vb.RemoteAddr {
+		buf.WriteString(strings.ToLower(r.RemoteAddr) + sep)
+	}
+	if vb.Method {
+		buf.WriteString(strings.ToLower(r.Method) + sep)
+	}
+	for _, h := range vb.Headers {
+		buf.WriteString(strings.ToLower(r.Header.Get(h)) + sep)
+	}
+	if vb.Path {
+		buf.WriteString(r.URL.Path + sep)
+	}
+	for _, p := range vb.Params {
+		buf.WriteString(r.FormValue(p) + sep)
+	}
+	for _, c := range vb.Cookies {
+		ck, err := r.Cookie(c)
+		if err == nil {
+			buf.WriteString(ck.Value)
+		}
+		buf.WriteString(sep) // Write the separator anyway, whether or not the cookie exists
+	}
+	return buf.String()
+}
diff --git a/vendor/gopkg.in/yaml.v2/.travis.yml b/vendor/gopkg.in/yaml.v2/.travis.yml
new file mode 100644
index 000000000..004172a2e
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/.travis.yml
@@ -0,0 +1,9 @@
+language: go
+
+go:
+    - 1.4
+    - 1.5
+    - 1.6
+    - tip
+
+go_import_path: gopkg.in/yaml.v2
diff --git a/vendor/gopkg.in/yaml.v2/LICENSE b/vendor/gopkg.in/yaml.v2/LICENSE
new file mode 100644
index 000000000..a68e67f01
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/LICENSE
@@ -0,0 +1,188 @@
+
+Copyright (c) 2011-2014 - Canonical Inc.
+
+This software is licensed under the LGPLv3, included below.
+
+As a special exception to the GNU Lesser General Public License version 3
+("LGPL3"), the copyright holders of this Library give you permission to
+convey to a third party a Combined Work that links statically or dynamically
+to this Library without providing any Minimal Corresponding Source or
+Minimal Application Code as set out in 4d or providing the installation
+information set out in section 4e, provided that you comply with the other
+provisions of LGPL3 and provided that you meet, for the Application the
+terms and conditions of the license(s) which apply to the Application.
+
+Except as stated in this special exception, the provisions of LGPL3 will
+continue to comply in full to this Library. If you modify this Library, you
+may apply this exception to your version of this Library, but you are not
+obliged to do so. If you do not wish to do so, delete this exception
+statement from your version. This exception does not (and cannot) modify any
+license terms which apply to the Application, with which you must still
+comply.
+
+
+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+   a) under this License, provided that you make a good faith effort to
+   ensure that, in the event an Application does not supply the
+   function or data, the facility still operates, and performs
+   whatever part of its purpose remains meaningful, or
+
+   b) under the GNU GPL, with none of the additional permissions of
+   this License applicable to that copy.
+
+  3. Object Code Incorporating Material from Library Header Files.
+
+  The object code form of an Application may incorporate material from
+a header file that is part of the Library.  You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the object code with a copy of the GNU GPL and this license
+   document.
+
+  4. Combined Works.
+
+  You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the Combined Work with a copy of the GNU GPL and this license
+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
+
+   d) Do one of the following:
+
+       0) Convey the Minimal Corresponding Source under the terms of this
+       License, and the Corresponding Application Code in a form
+       suitable for, and under terms that permit, the user to
+       recombine or relink the Application with a modified version of
+       the Linked Version to produce a modified Combined Work, in the
+       manner specified by section 6 of the GNU GPL for conveying
+       Corresponding Source.
+
+       1) Use a suitable shared library mechanism for linking with the
+       Library.  A suitable mechanism is one that (a) uses at run time
+       a copy of the Library already present on the user's computer
+       system, and (b) will operate properly with a modified version
+       of the Library that is interface-compatible with the Linked
+       Version.
+
+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
+   GNU GPL, and only to the extent that such information is
+   necessary to install and execute a modified version of the
+   Combined Work produced by recombining or relinking the
+   Application with a modified version of the Linked Version. (If
+   you use option 4d0, the Installation Information must accompany
+   the Minimal Corresponding Source and Corresponding Application
+   Code. If you use option 4d1, you must provide the Installation
+   Information in the manner specified by section 6 of the GNU GPL
+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.
diff --git a/vendor/gopkg.in/yaml.v2/LICENSE.libyaml b/vendor/gopkg.in/yaml.v2/LICENSE.libyaml
new file mode 100644
index 000000000..8da58fbf6
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/LICENSE.libyaml
@@ -0,0 +1,31 @@
+The following files were ported to Go from C files of libyaml, and thus
+are still covered by their original copyright and license:
+
+    apic.go
+    emitterc.go
+    parserc.go
+    readerc.go
+    scannerc.go
+    writerc.go
+    yamlh.go
+    yamlprivateh.go
+
+Copyright (c) 2006 Kirill Simonov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/vendor/gopkg.in/yaml.v2/README.md b/vendor/gopkg.in/yaml.v2/README.md
new file mode 100644
index 000000000..7b8bd8670
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/README.md
@@ -0,0 +1,131 @@
+# YAML support for the Go language
+
+Introduction
+------------
+
+The yaml package enables Go programs to comfortably encode and decode YAML
+values. It was developed within [Canonical](https://www.canonical.com) as
+part of the [juju](https://juju.ubuntu.com) project, and is based on a
+pure Go port of the well-known [libyaml](http://pyyaml.org/wiki/LibYAML)
+C library to parse and generate YAML data quickly and reliably.
+
+Compatibility
+-------------
+
+The yaml package supports most of YAML 1.1 and 1.2, including support for
+anchors, tags, map merging, etc. Multi-document unmarshalling is not yet
+implemented, and base-60 floats from YAML 1.1 are purposefully not
+supported since they're a poor design and are gone in YAML 1.2.
+
+Installation and usage
+----------------------
+
+The import path for the package is *gopkg.in/yaml.v2*.
+
+To install it, run:
+
+    go get gopkg.in/yaml.v2
+
+API documentation
+-----------------
+
+If opened in a browser, the import path itself leads to the API documentation:
+
+  * [https://gopkg.in/yaml.v2](https://gopkg.in/yaml.v2)
+
+API stability
+-------------
+
+The package API for yaml v2 will remain stable as described in [gopkg.in](https://gopkg.in).
+
+
+License
+-------
+
+The yaml package is licensed under the LGPL with an exception that allows it to be linked statically. Please see the LICENSE file for details.
+
+
+Example
+-------
+
+```Go
+package main
+
+import (
+        "fmt"
+        "log"
+
+        "gopkg.in/yaml.v2"
+)
+
+var data = `
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+`
+
+type T struct {
+        A string
+        B struct {
+                RenamedC int   `yaml:"c"`
+                D        []int `yaml:",flow"`
+        }
+}
+
+func main() {
+        t := T{}
+    
+        err := yaml.Unmarshal([]byte(data), &t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t:\n%v\n\n", t)
+    
+        d, err := yaml.Marshal(&t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t dump:\n%s\n\n", string(d))
+    
+        m := make(map[interface{}]interface{})
+    
+        err = yaml.Unmarshal([]byte(data), &m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m:\n%v\n\n", m)
+    
+        d, err = yaml.Marshal(&m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m dump:\n%s\n\n", string(d))
+}
+```
+
+This example will generate the following output:
+
+```
+--- t:
+{Easy! {2 [3 4]}}
+
+--- t dump:
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+
+
+--- m:
+map[a:Easy! b:map[c:2 d:[3 4]]]
+
+--- m dump:
+a: Easy!
+b:
+  c: 2
+  d:
+  - 3
+  - 4
+```
+
diff --git a/vendor/gopkg.in/yaml.v2/apic.go b/vendor/gopkg.in/yaml.v2/apic.go
new file mode 100644
index 000000000..95ec014e8
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/apic.go
@@ -0,0 +1,742 @@
+package yaml
+
+import (
+	"io"
+	"os"
+)
+
+func yaml_insert_token(parser *yaml_parser_t, pos int, token *yaml_token_t) {
+	//fmt.Println("yaml_insert_token", "pos:", pos, "typ:", token.typ, "head:", parser.tokens_head, "len:", len(parser.tokens))
+
+	// Check if we can move the queue at the beginning of the buffer.
+	if parser.tokens_head > 0 && len(parser.tokens) == cap(parser.tokens) {
+		if parser.tokens_head != len(parser.tokens) {
+			copy(parser.tokens, parser.tokens[parser.tokens_head:])
+		}
+		parser.tokens = parser.tokens[:len(parser.tokens)-parser.tokens_head]
+		parser.tokens_head = 0
+	}
+	parser.tokens = append(parser.tokens, *token)
+	if pos < 0 {
+		return
+	}
+	copy(parser.tokens[parser.tokens_head+pos+1:], parser.tokens[parser.tokens_head+pos:])
+	parser.tokens[parser.tokens_head+pos] = *token
+}
+
+// Create a new parser object.
+func yaml_parser_initialize(parser *yaml_parser_t) bool {
+	*parser = yaml_parser_t{
+		raw_buffer: make([]byte, 0, input_raw_buffer_size),
+		buffer:     make([]byte, 0, input_buffer_size),
+	}
+	return true
+}
+
+// Destroy a parser object.
+func yaml_parser_delete(parser *yaml_parser_t) {
+	*parser = yaml_parser_t{}
+}
+
+// String read handler.
+func yaml_string_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	if parser.input_pos == len(parser.input) {
+		return 0, io.EOF
+	}
+	n = copy(buffer, parser.input[parser.input_pos:])
+	parser.input_pos += n
+	return n, nil
+}
+
+// File read handler.
+func yaml_file_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	return parser.input_file.Read(buffer)
+}
+
+// Set a string input.
+func yaml_parser_set_input_string(parser *yaml_parser_t, input []byte) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_string_read_handler
+	parser.input = input
+	parser.input_pos = 0
+}
+
+// Set a file input.
+func yaml_parser_set_input_file(parser *yaml_parser_t, file *os.File) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_file_read_handler
+	parser.input_file = file
+}
+
+// Set the source encoding.
+func yaml_parser_set_encoding(parser *yaml_parser_t, encoding yaml_encoding_t) {
+	if parser.encoding != yaml_ANY_ENCODING {
+		panic("must set the encoding only once")
+	}
+	parser.encoding = encoding
+}
+
+// Create a new emitter object.
+func yaml_emitter_initialize(emitter *yaml_emitter_t) bool {
+	*emitter = yaml_emitter_t{
+		buffer:     make([]byte, output_buffer_size),
+		raw_buffer: make([]byte, 0, output_raw_buffer_size),
+		states:     make([]yaml_emitter_state_t, 0, initial_stack_size),
+		events:     make([]yaml_event_t, 0, initial_queue_size),
+	}
+	return true
+}
+
+// Destroy an emitter object.
+func yaml_emitter_delete(emitter *yaml_emitter_t) {
+	*emitter = yaml_emitter_t{}
+}
+
+// String write handler.
+func yaml_string_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	*emitter.output_buffer = append(*emitter.output_buffer, buffer...)
+	return nil
+}
+
+// File write handler.
+func yaml_file_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	_, err := emitter.output_file.Write(buffer)
+	return err
+}
+
+// Set a string output.
+func yaml_emitter_set_output_string(emitter *yaml_emitter_t, output_buffer *[]byte) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_string_write_handler
+	emitter.output_buffer = output_buffer
+}
+
+// Set a file output.
+func yaml_emitter_set_output_file(emitter *yaml_emitter_t, file io.Writer) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_file_write_handler
+	emitter.output_file = file
+}
+
+// Set the output encoding.
+func yaml_emitter_set_encoding(emitter *yaml_emitter_t, encoding yaml_encoding_t) {
+	if emitter.encoding != yaml_ANY_ENCODING {
+		panic("must set the output encoding only once")
+	}
+	emitter.encoding = encoding
+}
+
+// Set the canonical output style.
+func yaml_emitter_set_canonical(emitter *yaml_emitter_t, canonical bool) {
+	emitter.canonical = canonical
+}
+
+//// Set the indentation increment.
+func yaml_emitter_set_indent(emitter *yaml_emitter_t, indent int) {
+	if indent < 2 || indent > 9 {
+		indent = 2
+	}
+	emitter.best_indent = indent
+}
+
+// Set the preferred line width.
+func yaml_emitter_set_width(emitter *yaml_emitter_t, width int) {
+	if width < 0 {
+		width = -1
+	}
+	emitter.best_width = width
+}
+
+// Set if unescaped non-ASCII characters are allowed.
+func yaml_emitter_set_unicode(emitter *yaml_emitter_t, unicode bool) {
+	emitter.unicode = unicode
+}
+
+// Set the preferred line break character.
+func yaml_emitter_set_break(emitter *yaml_emitter_t, line_break yaml_break_t) {
+	emitter.line_break = line_break
+}
+
+///*
+// * Destroy a token object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_token_delete(yaml_token_t *token)
+//{
+//    assert(token);  // Non-NULL token object expected.
+//
+//    switch (token.type)
+//    {
+//        case YAML_TAG_DIRECTIVE_TOKEN:
+//            yaml_free(token.data.tag_directive.handle);
+//            yaml_free(token.data.tag_directive.prefix);
+//            break;
+//
+//        case YAML_ALIAS_TOKEN:
+//            yaml_free(token.data.alias.value);
+//            break;
+//
+//        case YAML_ANCHOR_TOKEN:
+//            yaml_free(token.data.anchor.value);
+//            break;
+//
+//        case YAML_TAG_TOKEN:
+//            yaml_free(token.data.tag.handle);
+//            yaml_free(token.data.tag.suffix);
+//            break;
+//
+//        case YAML_SCALAR_TOKEN:
+//            yaml_free(token.data.scalar.value);
+//            break;
+//
+//        default:
+//            break;
+//    }
+//
+//    memset(token, 0, sizeof(yaml_token_t));
+//}
+//
+///*
+// * Check if a string is a valid UTF-8 sequence.
+// *
+// * Check 'reader.c' for more details on UTF-8 encoding.
+// */
+//
+//static int
+//yaml_check_utf8(yaml_char_t *start, size_t length)
+//{
+//    yaml_char_t *end = start+length;
+//    yaml_char_t *pointer = start;
+//
+//    while (pointer < end) {
+//        unsigned char octet;
+//        unsigned int width;
+//        unsigned int value;
+//        size_t k;
+//
+//        octet = pointer[0];
+//        width = (octet & 0x80) == 0x00 ? 1 :
+//                (octet & 0xE0) == 0xC0 ? 2 :
+//                (octet & 0xF0) == 0xE0 ? 3 :
+//                (octet & 0xF8) == 0xF0 ? 4 : 0;
+//        value = (octet & 0x80) == 0x00 ? octet & 0x7F :
+//                (octet & 0xE0) == 0xC0 ? octet & 0x1F :
+//                (octet & 0xF0) == 0xE0 ? octet & 0x0F :
+//                (octet & 0xF8) == 0xF0 ? octet & 0x07 : 0;
+//        if (!width) return 0;
+//        if (pointer+width > end) return 0;
+//        for (k = 1; k < width; k ++) {
+//            octet = pointer[k];
+//            if ((octet & 0xC0) != 0x80) return 0;
+//            value = (value << 6) + (octet & 0x3F);
+//        }
+//        if (!((width == 1) ||
+//            (width == 2 && value >= 0x80) ||
+//            (width == 3 && value >= 0x800) ||
+//            (width == 4 && value >= 0x10000))) return 0;
+//
+//        pointer += width;
+//    }
+//
+//    return 1;
+//}
+//
+
+// Create STREAM-START.
+func yaml_stream_start_event_initialize(event *yaml_event_t, encoding yaml_encoding_t) bool {
+	*event = yaml_event_t{
+		typ:      yaml_STREAM_START_EVENT,
+		encoding: encoding,
+	}
+	return true
+}
+
+// Create STREAM-END.
+func yaml_stream_end_event_initialize(event *yaml_event_t) bool {
+	*event = yaml_event_t{
+		typ: yaml_STREAM_END_EVENT,
+	}
+	return true
+}
+
+// Create DOCUMENT-START.
+func yaml_document_start_event_initialize(event *yaml_event_t, version_directive *yaml_version_directive_t,
+	tag_directives []yaml_tag_directive_t, implicit bool) bool {
+	*event = yaml_event_t{
+		typ:               yaml_DOCUMENT_START_EVENT,
+		version_directive: version_directive,
+		tag_directives:    tag_directives,
+		implicit:          implicit,
+	}
+	return true
+}
+
+// Create DOCUMENT-END.
+func yaml_document_end_event_initialize(event *yaml_event_t, implicit bool) bool {
+	*event = yaml_event_t{
+		typ:      yaml_DOCUMENT_END_EVENT,
+		implicit: implicit,
+	}
+	return true
+}
+
+///*
+// * Create ALIAS.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_alias_event_initialize(event *yaml_event_t, anchor *yaml_char_t)
+//{
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    anchor_copy *yaml_char_t = NULL
+//
+//    assert(event) // Non-NULL event object is expected.
+//    assert(anchor) // Non-NULL anchor is expected.
+//
+//    if (!yaml_check_utf8(anchor, strlen((char *)anchor))) return 0
+//
+//    anchor_copy = yaml_strdup(anchor)
+//    if (!anchor_copy)
+//        return 0
+//
+//    ALIAS_EVENT_INIT(*event, anchor_copy, mark, mark)
+//
+//    return 1
+//}
+
+// Create SCALAR.
+func yaml_scalar_event_initialize(event *yaml_event_t, anchor, tag, value []byte, plain_implicit, quoted_implicit bool, style yaml_scalar_style_t) bool {
+	*event = yaml_event_t{
+		typ:             yaml_SCALAR_EVENT,
+		anchor:          anchor,
+		tag:             tag,
+		value:           value,
+		implicit:        plain_implicit,
+		quoted_implicit: quoted_implicit,
+		style:           yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-START.
+func yaml_sequence_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_sequence_style_t) bool {
+	*event = yaml_event_t{
+		typ:      yaml_SEQUENCE_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-END.
+func yaml_sequence_end_event_initialize(event *yaml_event_t) bool {
+	*event = yaml_event_t{
+		typ: yaml_SEQUENCE_END_EVENT,
+	}
+	return true
+}
+
+// Create MAPPING-START.
+func yaml_mapping_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_mapping_style_t) bool {
+	*event = yaml_event_t{
+		typ:      yaml_MAPPING_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+	return true
+}
+
+// Create MAPPING-END.
+func yaml_mapping_end_event_initialize(event *yaml_event_t) bool {
+	*event = yaml_event_t{
+		typ: yaml_MAPPING_END_EVENT,
+	}
+	return true
+}
+
+// Destroy an event object.
+func yaml_event_delete(event *yaml_event_t) {
+	*event = yaml_event_t{}
+}
+
+///*
+// * Create a document object.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_initialize(document *yaml_document_t,
+//        version_directive *yaml_version_directive_t,
+//        tag_directives_start *yaml_tag_directive_t,
+//        tag_directives_end *yaml_tag_directive_t,
+//        start_implicit int, end_implicit int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    struct {
+//        start *yaml_node_t
+//        end *yaml_node_t
+//        top *yaml_node_t
+//    } nodes = { NULL, NULL, NULL }
+//    version_directive_copy *yaml_version_directive_t = NULL
+//    struct {
+//        start *yaml_tag_directive_t
+//        end *yaml_tag_directive_t
+//        top *yaml_tag_directive_t
+//    } tag_directives_copy = { NULL, NULL, NULL }
+//    value yaml_tag_directive_t = { NULL, NULL }
+//    mark yaml_mark_t = { 0, 0, 0 }
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert((tag_directives_start && tag_directives_end) ||
+//            (tag_directives_start == tag_directives_end))
+//                            // Valid tag directives are expected.
+//
+//    if (!STACK_INIT(&context, nodes, INITIAL_STACK_SIZE)) goto error
+//
+//    if (version_directive) {
+//        version_directive_copy = yaml_malloc(sizeof(yaml_version_directive_t))
+//        if (!version_directive_copy) goto error
+//        version_directive_copy.major = version_directive.major
+//        version_directive_copy.minor = version_directive.minor
+//    }
+//
+//    if (tag_directives_start != tag_directives_end) {
+//        tag_directive *yaml_tag_directive_t
+//        if (!STACK_INIT(&context, tag_directives_copy, INITIAL_STACK_SIZE))
+//            goto error
+//        for (tag_directive = tag_directives_start
+//                tag_directive != tag_directives_end; tag_directive ++) {
+//            assert(tag_directive.handle)
+//            assert(tag_directive.prefix)
+//            if (!yaml_check_utf8(tag_directive.handle,
+//                        strlen((char *)tag_directive.handle)))
+//                goto error
+//            if (!yaml_check_utf8(tag_directive.prefix,
+//                        strlen((char *)tag_directive.prefix)))
+//                goto error
+//            value.handle = yaml_strdup(tag_directive.handle)
+//            value.prefix = yaml_strdup(tag_directive.prefix)
+//            if (!value.handle || !value.prefix) goto error
+//            if (!PUSH(&context, tag_directives_copy, value))
+//                goto error
+//            value.handle = NULL
+//            value.prefix = NULL
+//        }
+//    }
+//
+//    DOCUMENT_INIT(*document, nodes.start, nodes.end, version_directive_copy,
+//            tag_directives_copy.start, tag_directives_copy.top,
+//            start_implicit, end_implicit, mark, mark)
+//
+//    return 1
+//
+//error:
+//    STACK_DEL(&context, nodes)
+//    yaml_free(version_directive_copy)
+//    while (!STACK_EMPTY(&context, tag_directives_copy)) {
+//        value yaml_tag_directive_t = POP(&context, tag_directives_copy)
+//        yaml_free(value.handle)
+//        yaml_free(value.prefix)
+//    }
+//    STACK_DEL(&context, tag_directives_copy)
+//    yaml_free(value.handle)
+//    yaml_free(value.prefix)
+//
+//    return 0
+//}
+//
+///*
+// * Destroy a document object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_document_delete(document *yaml_document_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    tag_directive *yaml_tag_directive_t
+//
+//    context.error = YAML_NO_ERROR // Eliminate a compliler warning.
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    while (!STACK_EMPTY(&context, document.nodes)) {
+//        node yaml_node_t = POP(&context, document.nodes)
+//        yaml_free(node.tag)
+//        switch (node.type) {
+//            case YAML_SCALAR_NODE:
+//                yaml_free(node.data.scalar.value)
+//                break
+//            case YAML_SEQUENCE_NODE:
+//                STACK_DEL(&context, node.data.sequence.items)
+//                break
+//            case YAML_MAPPING_NODE:
+//                STACK_DEL(&context, node.data.mapping.pairs)
+//                break
+//            default:
+//                assert(0) // Should not happen.
+//        }
+//    }
+//    STACK_DEL(&context, document.nodes)
+//
+//    yaml_free(document.version_directive)
+//    for (tag_directive = document.tag_directives.start
+//            tag_directive != document.tag_directives.end
+//            tag_directive++) {
+//        yaml_free(tag_directive.handle)
+//        yaml_free(tag_directive.prefix)
+//    }
+//    yaml_free(document.tag_directives.start)
+//
+//    memset(document, 0, sizeof(yaml_document_t))
+//}
+//
+///**
+// * Get a document node.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_node(document *yaml_document_t, index int)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (index > 0 && document.nodes.start + index <= document.nodes.top) {
+//        return document.nodes.start + index - 1
+//    }
+//    return NULL
+//}
+//
+///**
+// * Get the root object.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_root_node(document *yaml_document_t)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (document.nodes.top != document.nodes.start) {
+//        return document.nodes.start
+//    }
+//    return NULL
+//}
+//
+///*
+// * Add a scalar node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_scalar(document *yaml_document_t,
+//        tag *yaml_char_t, value *yaml_char_t, length int,
+//        style yaml_scalar_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    value_copy *yaml_char_t = NULL
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert(value) // Non-NULL value is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SCALAR_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (length < 0) {
+//        length = strlen((char *)value)
+//    }
+//
+//    if (!yaml_check_utf8(value, length)) goto error
+//    value_copy = yaml_malloc(length+1)
+//    if (!value_copy) goto error
+//    memcpy(value_copy, value, length)
+//    value_copy[length] = '\0'
+//
+//    SCALAR_NODE_INIT(node, tag_copy, value_copy, length, style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    yaml_free(tag_copy)
+//    yaml_free(value_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a sequence node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_sequence(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_sequence_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_item_t
+//        end *yaml_node_item_t
+//        top *yaml_node_item_t
+//    } items = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SEQUENCE_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, items, INITIAL_STACK_SIZE)) goto error
+//
+//    SEQUENCE_NODE_INIT(node, tag_copy, items.start, items.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, items)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a mapping node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_mapping(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_mapping_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_pair_t
+//        end *yaml_node_pair_t
+//        top *yaml_node_pair_t
+//    } pairs = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_MAPPING_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, pairs, INITIAL_STACK_SIZE)) goto error
+//
+//    MAPPING_NODE_INIT(node, tag_copy, pairs.start, pairs.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, pairs)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Append an item to a sequence node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_sequence_item(document *yaml_document_t,
+//        sequence int, item int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(sequence > 0
+//            && document.nodes.start + sequence <= document.nodes.top)
+//                            // Valid sequence id is required.
+//    assert(document.nodes.start[sequence-1].type == YAML_SEQUENCE_NODE)
+//                            // A sequence node is required.
+//    assert(item > 0 && document.nodes.start + item <= document.nodes.top)
+//                            // Valid item id is required.
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[sequence-1].data.sequence.items, item))
+//        return 0
+//
+//    return 1
+//}
+//
+///*
+// * Append a pair of a key and a value to a mapping node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_mapping_pair(document *yaml_document_t,
+//        mapping int, key int, value int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    pair yaml_node_pair_t
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(mapping > 0
+//            && document.nodes.start + mapping <= document.nodes.top)
+//                            // Valid mapping id is required.
+//    assert(document.nodes.start[mapping-1].type == YAML_MAPPING_NODE)
+//                            // A mapping node is required.
+//    assert(key > 0 && document.nodes.start + key <= document.nodes.top)
+//                            // Valid key id is required.
+//    assert(value > 0 && document.nodes.start + value <= document.nodes.top)
+//                            // Valid value id is required.
+//
+//    pair.key = key
+//    pair.value = value
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[mapping-1].data.mapping.pairs, pair))
+//        return 0
+//
+//    return 1
+//}
+//
+//
diff --git a/vendor/gopkg.in/yaml.v2/decode.go b/vendor/gopkg.in/yaml.v2/decode.go
new file mode 100644
index 000000000..085cddc44
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/decode.go
@@ -0,0 +1,683 @@
+package yaml
+
+import (
+	"encoding"
+	"encoding/base64"
+	"fmt"
+	"math"
+	"reflect"
+	"strconv"
+	"time"
+)
+
+const (
+	documentNode = 1 << iota
+	mappingNode
+	sequenceNode
+	scalarNode
+	aliasNode
+)
+
+type node struct {
+	kind         int
+	line, column int
+	tag          string
+	value        string
+	implicit     bool
+	children     []*node
+	anchors      map[string]*node
+}
+
+// ----------------------------------------------------------------------------
+// Parser, produces a node tree out of a libyaml event stream.
+
+type parser struct {
+	parser yaml_parser_t
+	event  yaml_event_t
+	doc    *node
+}
+
+func newParser(b []byte) *parser {
+	p := parser{}
+	if !yaml_parser_initialize(&p.parser) {
+		panic("failed to initialize YAML emitter")
+	}
+
+	if len(b) == 0 {
+		b = []byte{'\n'}
+	}
+
+	yaml_parser_set_input_string(&p.parser, b)
+
+	p.skip()
+	if p.event.typ != yaml_STREAM_START_EVENT {
+		panic("expected stream start event, got " + strconv.Itoa(int(p.event.typ)))
+	}
+	p.skip()
+	return &p
+}
+
+func (p *parser) destroy() {
+	if p.event.typ != yaml_NO_EVENT {
+		yaml_event_delete(&p.event)
+	}
+	yaml_parser_delete(&p.parser)
+}
+
+func (p *parser) skip() {
+	if p.event.typ != yaml_NO_EVENT {
+		if p.event.typ == yaml_STREAM_END_EVENT {
+			failf("attempted to go past the end of stream; corrupted value?")
+		}
+		yaml_event_delete(&p.event)
+	}
+	if !yaml_parser_parse(&p.parser, &p.event) {
+		p.fail()
+	}
+}
+
+func (p *parser) fail() {
+	var where string
+	var line int
+	if p.parser.problem_mark.line != 0 {
+		line = p.parser.problem_mark.line
+	} else if p.parser.context_mark.line != 0 {
+		line = p.parser.context_mark.line
+	}
+	if line != 0 {
+		where = "line " + strconv.Itoa(line) + ": "
+	}
+	var msg string
+	if len(p.parser.problem) > 0 {
+		msg = p.parser.problem
+	} else {
+		msg = "unknown problem parsing YAML content"
+	}
+	failf("%s%s", where, msg)
+}
+
+func (p *parser) anchor(n *node, anchor []byte) {
+	if anchor != nil {
+		p.doc.anchors[string(anchor)] = n
+	}
+}
+
+func (p *parser) parse() *node {
+	switch p.event.typ {
+	case yaml_SCALAR_EVENT:
+		return p.scalar()
+	case yaml_ALIAS_EVENT:
+		return p.alias()
+	case yaml_MAPPING_START_EVENT:
+		return p.mapping()
+	case yaml_SEQUENCE_START_EVENT:
+		return p.sequence()
+	case yaml_DOCUMENT_START_EVENT:
+		return p.document()
+	case yaml_STREAM_END_EVENT:
+		// Happens when attempting to decode an empty buffer.
+		return nil
+	default:
+		panic("attempted to parse unknown event: " + strconv.Itoa(int(p.event.typ)))
+	}
+	panic("unreachable")
+}
+
+func (p *parser) node(kind int) *node {
+	return &node{
+		kind:   kind,
+		line:   p.event.start_mark.line,
+		column: p.event.start_mark.column,
+	}
+}
+
+func (p *parser) document() *node {
+	n := p.node(documentNode)
+	n.anchors = make(map[string]*node)
+	p.doc = n
+	p.skip()
+	n.children = append(n.children, p.parse())
+	if p.event.typ != yaml_DOCUMENT_END_EVENT {
+		panic("expected end of document event but got " + strconv.Itoa(int(p.event.typ)))
+	}
+	p.skip()
+	return n
+}
+
+func (p *parser) alias() *node {
+	n := p.node(aliasNode)
+	n.value = string(p.event.anchor)
+	p.skip()
+	return n
+}
+
+func (p *parser) scalar() *node {
+	n := p.node(scalarNode)
+	n.value = string(p.event.value)
+	n.tag = string(p.event.tag)
+	n.implicit = p.event.implicit
+	p.anchor(n, p.event.anchor)
+	p.skip()
+	return n
+}
+
+func (p *parser) sequence() *node {
+	n := p.node(sequenceNode)
+	p.anchor(n, p.event.anchor)
+	p.skip()
+	for p.event.typ != yaml_SEQUENCE_END_EVENT {
+		n.children = append(n.children, p.parse())
+	}
+	p.skip()
+	return n
+}
+
+func (p *parser) mapping() *node {
+	n := p.node(mappingNode)
+	p.anchor(n, p.event.anchor)
+	p.skip()
+	for p.event.typ != yaml_MAPPING_END_EVENT {
+		n.children = append(n.children, p.parse(), p.parse())
+	}
+	p.skip()
+	return n
+}
+
+// ----------------------------------------------------------------------------
+// Decoder, unmarshals a node into a provided value.
+
+type decoder struct {
+	doc     *node
+	aliases map[string]bool
+	mapType reflect.Type
+	terrors []string
+}
+
+var (
+	mapItemType    = reflect.TypeOf(MapItem{})
+	durationType   = reflect.TypeOf(time.Duration(0))
+	defaultMapType = reflect.TypeOf(map[interface{}]interface{}{})
+	ifaceType      = defaultMapType.Elem()
+)
+
+func newDecoder() *decoder {
+	d := &decoder{mapType: defaultMapType}
+	d.aliases = make(map[string]bool)
+	return d
+}
+
+func (d *decoder) terror(n *node, tag string, out reflect.Value) {
+	if n.tag != "" {
+		tag = n.tag
+	}
+	value := n.value
+	if tag != yaml_SEQ_TAG && tag != yaml_MAP_TAG {
+		if len(value) > 10 {
+			value = " `" + value[:7] + "...`"
+		} else {
+			value = " `" + value + "`"
+		}
+	}
+	d.terrors = append(d.terrors, fmt.Sprintf("line %d: cannot unmarshal %s%s into %s", n.line+1, shortTag(tag), value, out.Type()))
+}
+
+func (d *decoder) callUnmarshaler(n *node, u Unmarshaler) (good bool) {
+	terrlen := len(d.terrors)
+	err := u.UnmarshalYAML(func(v interface{}) (err error) {
+		defer handleErr(&err)
+		d.unmarshal(n, reflect.ValueOf(v))
+		if len(d.terrors) > terrlen {
+			issues := d.terrors[terrlen:]
+			d.terrors = d.terrors[:terrlen]
+			return &TypeError{issues}
+		}
+		return nil
+	})
+	if e, ok := err.(*TypeError); ok {
+		d.terrors = append(d.terrors, e.Errors...)
+		return false
+	}
+	if err != nil {
+		fail(err)
+	}
+	return true
+}
+
+// d.prepare initializes and dereferences pointers and calls UnmarshalYAML
+// if a value is found to implement it.
+// It returns the initialized and dereferenced out value, whether
+// unmarshalling was already done by UnmarshalYAML, and if so whether
+// its types unmarshalled appropriately.
+//
+// If n holds a null value, prepare returns before doing anything.
+func (d *decoder) prepare(n *node, out reflect.Value) (newout reflect.Value, unmarshaled, good bool) {
+	if n.tag == yaml_NULL_TAG || n.kind == scalarNode && n.tag == "" && (n.value == "null" || n.value == "") {
+		return out, false, false
+	}
+	again := true
+	for again {
+		again = false
+		if out.Kind() == reflect.Ptr {
+			if out.IsNil() {
+				out.Set(reflect.New(out.Type().Elem()))
+			}
+			out = out.Elem()
+			again = true
+		}
+		if out.CanAddr() {
+			if u, ok := out.Addr().Interface().(Unmarshaler); ok {
+				good = d.callUnmarshaler(n, u)
+				return out, true, good
+			}
+		}
+	}
+	return out, false, false
+}
+
+func (d *decoder) unmarshal(n *node, out reflect.Value) (good bool) {
+	switch n.kind {
+	case documentNode:
+		return d.document(n, out)
+	case aliasNode:
+		return d.alias(n, out)
+	}
+	out, unmarshaled, good := d.prepare(n, out)
+	if unmarshaled {
+		return good
+	}
+	switch n.kind {
+	case scalarNode:
+		good = d.scalar(n, out)
+	case mappingNode:
+		good = d.mapping(n, out)
+	case sequenceNode:
+		good = d.sequence(n, out)
+	default:
+		panic("internal error: unknown node kind: " + strconv.Itoa(n.kind))
+	}
+	return good
+}
+
+func (d *decoder) document(n *node, out reflect.Value) (good bool) {
+	if len(n.children) == 1 {
+		d.doc = n
+		d.unmarshal(n.children[0], out)
+		return true
+	}
+	return false
+}
+
+func (d *decoder) alias(n *node, out reflect.Value) (good bool) {
+	an, ok := d.doc.anchors[n.value]
+	if !ok {
+		failf("unknown anchor '%s' referenced", n.value)
+	}
+	if d.aliases[n.value] {
+		failf("anchor '%s' value contains itself", n.value)
+	}
+	d.aliases[n.value] = true
+	good = d.unmarshal(an, out)
+	delete(d.aliases, n.value)
+	return good
+}
+
+var zeroValue reflect.Value
+
+func resetMap(out reflect.Value) {
+	for _, k := range out.MapKeys() {
+		out.SetMapIndex(k, zeroValue)
+	}
+}
+
+func (d *decoder) scalar(n *node, out reflect.Value) (good bool) {
+	var tag string
+	var resolved interface{}
+	if n.tag == "" && !n.implicit {
+		tag = yaml_STR_TAG
+		resolved = n.value
+	} else {
+		tag, resolved = resolve(n.tag, n.value)
+		if tag == yaml_BINARY_TAG {
+			data, err := base64.StdEncoding.DecodeString(resolved.(string))
+			if err != nil {
+				failf("!!binary value contains invalid base64 data")
+			}
+			resolved = string(data)
+		}
+	}
+	if resolved == nil {
+		if out.Kind() == reflect.Map && !out.CanAddr() {
+			resetMap(out)
+		} else {
+			out.Set(reflect.Zero(out.Type()))
+		}
+		return true
+	}
+	if s, ok := resolved.(string); ok && out.CanAddr() {
+		if u, ok := out.Addr().Interface().(encoding.TextUnmarshaler); ok {
+			err := u.UnmarshalText([]byte(s))
+			if err != nil {
+				fail(err)
+			}
+			return true
+		}
+	}
+	switch out.Kind() {
+	case reflect.String:
+		if tag == yaml_BINARY_TAG {
+			out.SetString(resolved.(string))
+			good = true
+		} else if resolved != nil {
+			out.SetString(n.value)
+			good = true
+		}
+	case reflect.Interface:
+		if resolved == nil {
+			out.Set(reflect.Zero(out.Type()))
+		} else {
+			out.Set(reflect.ValueOf(resolved))
+		}
+		good = true
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		switch resolved := resolved.(type) {
+		case int:
+			if !out.OverflowInt(int64(resolved)) {
+				out.SetInt(int64(resolved))
+				good = true
+			}
+		case int64:
+			if !out.OverflowInt(resolved) {
+				out.SetInt(resolved)
+				good = true
+			}
+		case uint64:
+			if resolved <= math.MaxInt64 && !out.OverflowInt(int64(resolved)) {
+				out.SetInt(int64(resolved))
+				good = true
+			}
+		case float64:
+			if resolved <= math.MaxInt64 && !out.OverflowInt(int64(resolved)) {
+				out.SetInt(int64(resolved))
+				good = true
+			}
+		case string:
+			if out.Type() == durationType {
+				d, err := time.ParseDuration(resolved)
+				if err == nil {
+					out.SetInt(int64(d))
+					good = true
+				}
+			}
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		switch resolved := resolved.(type) {
+		case int:
+			if resolved >= 0 && !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				good = true
+			}
+		case int64:
+			if resolved >= 0 && !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				good = true
+			}
+		case uint64:
+			if !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				good = true
+			}
+		case float64:
+			if resolved <= math.MaxUint64 && !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				good = true
+			}
+		}
+	case reflect.Bool:
+		switch resolved := resolved.(type) {
+		case bool:
+			out.SetBool(resolved)
+			good = true
+		}
+	case reflect.Float32, reflect.Float64:
+		switch resolved := resolved.(type) {
+		case int:
+			out.SetFloat(float64(resolved))
+			good = true
+		case int64:
+			out.SetFloat(float64(resolved))
+			good = true
+		case uint64:
+			out.SetFloat(float64(resolved))
+			good = true
+		case float64:
+			out.SetFloat(resolved)
+			good = true
+		}
+	case reflect.Ptr:
+		if out.Type().Elem() == reflect.TypeOf(resolved) {
+			// TODO DOes this make sense? When is out a Ptr except when decoding a nil value?
+			elem := reflect.New(out.Type().Elem())
+			elem.Elem().Set(reflect.ValueOf(resolved))
+			out.Set(elem)
+			good = true
+		}
+	}
+	if !good {
+		d.terror(n, tag, out)
+	}
+	return good
+}
+
+func settableValueOf(i interface{}) reflect.Value {
+	v := reflect.ValueOf(i)
+	sv := reflect.New(v.Type()).Elem()
+	sv.Set(v)
+	return sv
+}
+
+func (d *decoder) sequence(n *node, out reflect.Value) (good bool) {
+	l := len(n.children)
+
+	var iface reflect.Value
+	switch out.Kind() {
+	case reflect.Slice:
+		out.Set(reflect.MakeSlice(out.Type(), l, l))
+	case reflect.Interface:
+		// No type hints. Will have to use a generic sequence.
+		iface = out
+		out = settableValueOf(make([]interface{}, l))
+	default:
+		d.terror(n, yaml_SEQ_TAG, out)
+		return false
+	}
+	et := out.Type().Elem()
+
+	j := 0
+	for i := 0; i < l; i++ {
+		e := reflect.New(et).Elem()
+		if ok := d.unmarshal(n.children[i], e); ok {
+			out.Index(j).Set(e)
+			j++
+		}
+	}
+	out.Set(out.Slice(0, j))
+	if iface.IsValid() {
+		iface.Set(out)
+	}
+	return true
+}
+
+func (d *decoder) mapping(n *node, out reflect.Value) (good bool) {
+	switch out.Kind() {
+	case reflect.Struct:
+		return d.mappingStruct(n, out)
+	case reflect.Slice:
+		return d.mappingSlice(n, out)
+	case reflect.Map:
+		// okay
+	case reflect.Interface:
+		if d.mapType.Kind() == reflect.Map {
+			iface := out
+			out = reflect.MakeMap(d.mapType)
+			iface.Set(out)
+		} else {
+			slicev := reflect.New(d.mapType).Elem()
+			if !d.mappingSlice(n, slicev) {
+				return false
+			}
+			out.Set(slicev)
+			return true
+		}
+	default:
+		d.terror(n, yaml_MAP_TAG, out)
+		return false
+	}
+	outt := out.Type()
+	kt := outt.Key()
+	et := outt.Elem()
+
+	mapType := d.mapType
+	if outt.Key() == ifaceType && outt.Elem() == ifaceType {
+		d.mapType = outt
+	}
+
+	if out.IsNil() {
+		out.Set(reflect.MakeMap(outt))
+	}
+	l := len(n.children)
+	for i := 0; i < l; i += 2 {
+		if isMerge(n.children[i]) {
+			d.merge(n.children[i+1], out)
+			continue
+		}
+		k := reflect.New(kt).Elem()
+		if d.unmarshal(n.children[i], k) {
+			kkind := k.Kind()
+			if kkind == reflect.Interface {
+				kkind = k.Elem().Kind()
+			}
+			if kkind == reflect.Map || kkind == reflect.Slice {
+				failf("invalid map key: %#v", k.Interface())
+			}
+			e := reflect.New(et).Elem()
+			if d.unmarshal(n.children[i+1], e) {
+				out.SetMapIndex(k, e)
+			}
+		}
+	}
+	d.mapType = mapType
+	return true
+}
+
+func (d *decoder) mappingSlice(n *node, out reflect.Value) (good bool) {
+	outt := out.Type()
+	if outt.Elem() != mapItemType {
+		d.terror(n, yaml_MAP_TAG, out)
+		return false
+	}
+
+	mapType := d.mapType
+	d.mapType = outt
+
+	var slice []MapItem
+	var l = len(n.children)
+	for i := 0; i < l; i += 2 {
+		if isMerge(n.children[i]) {
+			d.merge(n.children[i+1], out)
+			continue
+		}
+		item := MapItem{}
+		k := reflect.ValueOf(&item.Key).Elem()
+		if d.unmarshal(n.children[i], k) {
+			v := reflect.ValueOf(&item.Value).Elem()
+			if d.unmarshal(n.children[i+1], v) {
+				slice = append(slice, item)
+			}
+		}
+	}
+	out.Set(reflect.ValueOf(slice))
+	d.mapType = mapType
+	return true
+}
+
+func (d *decoder) mappingStruct(n *node, out reflect.Value) (good bool) {
+	sinfo, err := getStructInfo(out.Type())
+	if err != nil {
+		panic(err)
+	}
+	name := settableValueOf("")
+	l := len(n.children)
+
+	var inlineMap reflect.Value
+	var elemType reflect.Type
+	if sinfo.InlineMap != -1 {
+		inlineMap = out.Field(sinfo.InlineMap)
+		inlineMap.Set(reflect.New(inlineMap.Type()).Elem())
+		elemType = inlineMap.Type().Elem()
+	}
+
+	for i := 0; i < l; i += 2 {
+		ni := n.children[i]
+		if isMerge(ni) {
+			d.merge(n.children[i+1], out)
+			continue
+		}
+		if !d.unmarshal(ni, name) {
+			continue
+		}
+		if info, ok := sinfo.FieldsMap[name.String()]; ok {
+			var field reflect.Value
+			if info.Inline == nil {
+				field = out.Field(info.Num)
+			} else {
+				field = out.FieldByIndex(info.Inline)
+			}
+			d.unmarshal(n.children[i+1], field)
+		} else if sinfo.InlineMap != -1 {
+			if inlineMap.IsNil() {
+				inlineMap.Set(reflect.MakeMap(inlineMap.Type()))
+			}
+			value := reflect.New(elemType).Elem()
+			d.unmarshal(n.children[i+1], value)
+			inlineMap.SetMapIndex(name, value)
+		}
+	}
+	return true
+}
+
+func failWantMap() {
+	failf("map merge requires map or sequence of maps as the value")
+}
+
+func (d *decoder) merge(n *node, out reflect.Value) {
+	switch n.kind {
+	case mappingNode:
+		d.unmarshal(n, out)
+	case aliasNode:
+		an, ok := d.doc.anchors[n.value]
+		if ok && an.kind != mappingNode {
+			failWantMap()
+		}
+		d.unmarshal(n, out)
+	case sequenceNode:
+		// Step backwards as earlier nodes take precedence.
+		for i := len(n.children) - 1; i >= 0; i-- {
+			ni := n.children[i]
+			if ni.kind == aliasNode {
+				an, ok := d.doc.anchors[ni.value]
+				if ok && an.kind != mappingNode {
+					failWantMap()
+				}
+			} else if ni.kind != mappingNode {
+				failWantMap()
+			}
+			d.unmarshal(ni, out)
+		}
+	default:
+		failWantMap()
+	}
+}
+
+func isMerge(n *node) bool {
+	return n.kind == scalarNode && n.value == "<<" && (n.implicit == true || n.tag == yaml_MERGE_TAG)
+}
diff --git a/vendor/gopkg.in/yaml.v2/emitterc.go b/vendor/gopkg.in/yaml.v2/emitterc.go
new file mode 100644
index 000000000..2befd553e
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/emitterc.go
@@ -0,0 +1,1685 @@
+package yaml
+
+import (
+	"bytes"
+)
+
+// Flush the buffer if needed.
+func flush(emitter *yaml_emitter_t) bool {
+	if emitter.buffer_pos+5 >= len(emitter.buffer) {
+		return yaml_emitter_flush(emitter)
+	}
+	return true
+}
+
+// Put a character to the output buffer.
+func put(emitter *yaml_emitter_t, value byte) bool {
+	if emitter.buffer_pos+5 >= len(emitter.buffer) && !yaml_emitter_flush(emitter) {
+		return false
+	}
+	emitter.buffer[emitter.buffer_pos] = value
+	emitter.buffer_pos++
+	emitter.column++
+	return true
+}
+
+// Put a line break to the output buffer.
+func put_break(emitter *yaml_emitter_t) bool {
+	if emitter.buffer_pos+5 >= len(emitter.buffer) && !yaml_emitter_flush(emitter) {
+		return false
+	}
+	switch emitter.line_break {
+	case yaml_CR_BREAK:
+		emitter.buffer[emitter.buffer_pos] = '\r'
+		emitter.buffer_pos += 1
+	case yaml_LN_BREAK:
+		emitter.buffer[emitter.buffer_pos] = '\n'
+		emitter.buffer_pos += 1
+	case yaml_CRLN_BREAK:
+		emitter.buffer[emitter.buffer_pos+0] = '\r'
+		emitter.buffer[emitter.buffer_pos+1] = '\n'
+		emitter.buffer_pos += 2
+	default:
+		panic("unknown line break setting")
+	}
+	emitter.column = 0
+	emitter.line++
+	return true
+}
+
+// Copy a character from a string into buffer.
+func write(emitter *yaml_emitter_t, s []byte, i *int) bool {
+	if emitter.buffer_pos+5 >= len(emitter.buffer) && !yaml_emitter_flush(emitter) {
+		return false
+	}
+	p := emitter.buffer_pos
+	w := width(s[*i])
+	switch w {
+	case 4:
+		emitter.buffer[p+3] = s[*i+3]
+		fallthrough
+	case 3:
+		emitter.buffer[p+2] = s[*i+2]
+		fallthrough
+	case 2:
+		emitter.buffer[p+1] = s[*i+1]
+		fallthrough
+	case 1:
+		emitter.buffer[p+0] = s[*i+0]
+	default:
+		panic("unknown character width")
+	}
+	emitter.column++
+	emitter.buffer_pos += w
+	*i += w
+	return true
+}
+
+// Write a whole string into buffer.
+func write_all(emitter *yaml_emitter_t, s []byte) bool {
+	for i := 0; i < len(s); {
+		if !write(emitter, s, &i) {
+			return false
+		}
+	}
+	return true
+}
+
+// Copy a line break character from a string into buffer.
+func write_break(emitter *yaml_emitter_t, s []byte, i *int) bool {
+	if s[*i] == '\n' {
+		if !put_break(emitter) {
+			return false
+		}
+		*i++
+	} else {
+		if !write(emitter, s, i) {
+			return false
+		}
+		emitter.column = 0
+		emitter.line++
+	}
+	return true
+}
+
+// Set an emitter error and return false.
+func yaml_emitter_set_emitter_error(emitter *yaml_emitter_t, problem string) bool {
+	emitter.error = yaml_EMITTER_ERROR
+	emitter.problem = problem
+	return false
+}
+
+// Emit an event.
+func yaml_emitter_emit(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	emitter.events = append(emitter.events, *event)
+	for !yaml_emitter_need_more_events(emitter) {
+		event := &emitter.events[emitter.events_head]
+		if !yaml_emitter_analyze_event(emitter, event) {
+			return false
+		}
+		if !yaml_emitter_state_machine(emitter, event) {
+			return false
+		}
+		yaml_event_delete(event)
+		emitter.events_head++
+	}
+	return true
+}
+
+// Check if we need to accumulate more events before emitting.
+//
+// We accumulate extra
+//  - 1 event for DOCUMENT-START
+//  - 2 events for SEQUENCE-START
+//  - 3 events for MAPPING-START
+//
+func yaml_emitter_need_more_events(emitter *yaml_emitter_t) bool {
+	if emitter.events_head == len(emitter.events) {
+		return true
+	}
+	var accumulate int
+	switch emitter.events[emitter.events_head].typ {
+	case yaml_DOCUMENT_START_EVENT:
+		accumulate = 1
+		break
+	case yaml_SEQUENCE_START_EVENT:
+		accumulate = 2
+		break
+	case yaml_MAPPING_START_EVENT:
+		accumulate = 3
+		break
+	default:
+		return false
+	}
+	if len(emitter.events)-emitter.events_head > accumulate {
+		return false
+	}
+	var level int
+	for i := emitter.events_head; i < len(emitter.events); i++ {
+		switch emitter.events[i].typ {
+		case yaml_STREAM_START_EVENT, yaml_DOCUMENT_START_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT:
+			level++
+		case yaml_STREAM_END_EVENT, yaml_DOCUMENT_END_EVENT, yaml_SEQUENCE_END_EVENT, yaml_MAPPING_END_EVENT:
+			level--
+		}
+		if level == 0 {
+			return false
+		}
+	}
+	return true
+}
+
+// Append a directive to the directives stack.
+func yaml_emitter_append_tag_directive(emitter *yaml_emitter_t, value *yaml_tag_directive_t, allow_duplicates bool) bool {
+	for i := 0; i < len(emitter.tag_directives); i++ {
+		if bytes.Equal(value.handle, emitter.tag_directives[i].handle) {
+			if allow_duplicates {
+				return true
+			}
+			return yaml_emitter_set_emitter_error(emitter, "duplicate %TAG directive")
+		}
+	}
+
+	// [Go] Do we actually need to copy this given garbage collection
+	// and the lack of deallocating destructors?
+	tag_copy := yaml_tag_directive_t{
+		handle: make([]byte, len(value.handle)),
+		prefix: make([]byte, len(value.prefix)),
+	}
+	copy(tag_copy.handle, value.handle)
+	copy(tag_copy.prefix, value.prefix)
+	emitter.tag_directives = append(emitter.tag_directives, tag_copy)
+	return true
+}
+
+// Increase the indentation level.
+func yaml_emitter_increase_indent(emitter *yaml_emitter_t, flow, indentless bool) bool {
+	emitter.indents = append(emitter.indents, emitter.indent)
+	if emitter.indent < 0 {
+		if flow {
+			emitter.indent = emitter.best_indent
+		} else {
+			emitter.indent = 0
+		}
+	} else if !indentless {
+		emitter.indent += emitter.best_indent
+	}
+	return true
+}
+
+// State dispatcher.
+func yaml_emitter_state_machine(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	switch emitter.state {
+	default:
+	case yaml_EMIT_STREAM_START_STATE:
+		return yaml_emitter_emit_stream_start(emitter, event)
+
+	case yaml_EMIT_FIRST_DOCUMENT_START_STATE:
+		return yaml_emitter_emit_document_start(emitter, event, true)
+
+	case yaml_EMIT_DOCUMENT_START_STATE:
+		return yaml_emitter_emit_document_start(emitter, event, false)
+
+	case yaml_EMIT_DOCUMENT_CONTENT_STATE:
+		return yaml_emitter_emit_document_content(emitter, event)
+
+	case yaml_EMIT_DOCUMENT_END_STATE:
+		return yaml_emitter_emit_document_end(emitter, event)
+
+	case yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE:
+		return yaml_emitter_emit_flow_sequence_item(emitter, event, true)
+
+	case yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE:
+		return yaml_emitter_emit_flow_sequence_item(emitter, event, false)
+
+	case yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE:
+		return yaml_emitter_emit_flow_mapping_key(emitter, event, true)
+
+	case yaml_EMIT_FLOW_MAPPING_KEY_STATE:
+		return yaml_emitter_emit_flow_mapping_key(emitter, event, false)
+
+	case yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE:
+		return yaml_emitter_emit_flow_mapping_value(emitter, event, true)
+
+	case yaml_EMIT_FLOW_MAPPING_VALUE_STATE:
+		return yaml_emitter_emit_flow_mapping_value(emitter, event, false)
+
+	case yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE:
+		return yaml_emitter_emit_block_sequence_item(emitter, event, true)
+
+	case yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE:
+		return yaml_emitter_emit_block_sequence_item(emitter, event, false)
+
+	case yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE:
+		return yaml_emitter_emit_block_mapping_key(emitter, event, true)
+
+	case yaml_EMIT_BLOCK_MAPPING_KEY_STATE:
+		return yaml_emitter_emit_block_mapping_key(emitter, event, false)
+
+	case yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE:
+		return yaml_emitter_emit_block_mapping_value(emitter, event, true)
+
+	case yaml_EMIT_BLOCK_MAPPING_VALUE_STATE:
+		return yaml_emitter_emit_block_mapping_value(emitter, event, false)
+
+	case yaml_EMIT_END_STATE:
+		return yaml_emitter_set_emitter_error(emitter, "expected nothing after STREAM-END")
+	}
+	panic("invalid emitter state")
+}
+
+// Expect STREAM-START.
+func yaml_emitter_emit_stream_start(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	if event.typ != yaml_STREAM_START_EVENT {
+		return yaml_emitter_set_emitter_error(emitter, "expected STREAM-START")
+	}
+	if emitter.encoding == yaml_ANY_ENCODING {
+		emitter.encoding = event.encoding
+		if emitter.encoding == yaml_ANY_ENCODING {
+			emitter.encoding = yaml_UTF8_ENCODING
+		}
+	}
+	if emitter.best_indent < 2 || emitter.best_indent > 9 {
+		emitter.best_indent = 2
+	}
+	if emitter.best_width >= 0 && emitter.best_width <= emitter.best_indent*2 {
+		emitter.best_width = 80
+	}
+	if emitter.best_width < 0 {
+		emitter.best_width = 1<<31 - 1
+	}
+	if emitter.line_break == yaml_ANY_BREAK {
+		emitter.line_break = yaml_LN_BREAK
+	}
+
+	emitter.indent = -1
+	emitter.line = 0
+	emitter.column = 0
+	emitter.whitespace = true
+	emitter.indention = true
+
+	if emitter.encoding != yaml_UTF8_ENCODING {
+		if !yaml_emitter_write_bom(emitter) {
+			return false
+		}
+	}
+	emitter.state = yaml_EMIT_FIRST_DOCUMENT_START_STATE
+	return true
+}
+
+// Expect DOCUMENT-START or STREAM-END.
+func yaml_emitter_emit_document_start(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
+
+	if event.typ == yaml_DOCUMENT_START_EVENT {
+
+		if event.version_directive != nil {
+			if !yaml_emitter_analyze_version_directive(emitter, event.version_directive) {
+				return false
+			}
+		}
+
+		for i := 0; i < len(event.tag_directives); i++ {
+			tag_directive := &event.tag_directives[i]
+			if !yaml_emitter_analyze_tag_directive(emitter, tag_directive) {
+				return false
+			}
+			if !yaml_emitter_append_tag_directive(emitter, tag_directive, false) {
+				return false
+			}
+		}
+
+		for i := 0; i < len(default_tag_directives); i++ {
+			tag_directive := &default_tag_directives[i]
+			if !yaml_emitter_append_tag_directive(emitter, tag_directive, true) {
+				return false
+			}
+		}
+
+		implicit := event.implicit
+		if !first || emitter.canonical {
+			implicit = false
+		}
+
+		if emitter.open_ended && (event.version_directive != nil || len(event.tag_directives) > 0) {
+			if !yaml_emitter_write_indicator(emitter, []byte("..."), true, false, false) {
+				return false
+			}
+			if !yaml_emitter_write_indent(emitter) {
+				return false
+			}
+		}
+
+		if event.version_directive != nil {
+			implicit = false
+			if !yaml_emitter_write_indicator(emitter, []byte("%YAML"), true, false, false) {
+				return false
+			}
+			if !yaml_emitter_write_indicator(emitter, []byte("1.1"), true, false, false) {
+				return false
+			}
+			if !yaml_emitter_write_indent(emitter) {
+				return false
+			}
+		}
+
+		if len(event.tag_directives) > 0 {
+			implicit = false
+			for i := 0; i < len(event.tag_directives); i++ {
+				tag_directive := &event.tag_directives[i]
+				if !yaml_emitter_write_indicator(emitter, []byte("%TAG"), true, false, false) {
+					return false
+				}
+				if !yaml_emitter_write_tag_handle(emitter, tag_directive.handle) {
+					return false
+				}
+				if !yaml_emitter_write_tag_content(emitter, tag_directive.prefix, true) {
+					return false
+				}
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+			}
+		}
+
+		if yaml_emitter_check_empty_document(emitter) {
+			implicit = false
+		}
+		if !implicit {
+			if !yaml_emitter_write_indent(emitter) {
+				return false
+			}
+			if !yaml_emitter_write_indicator(emitter, []byte("---"), true, false, false) {
+				return false
+			}
+			if emitter.canonical {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+			}
+		}
+
+		emitter.state = yaml_EMIT_DOCUMENT_CONTENT_STATE
+		return true
+	}
+
+	if event.typ == yaml_STREAM_END_EVENT {
+		if emitter.open_ended {
+			if !yaml_emitter_write_indicator(emitter, []byte("..."), true, false, false) {
+				return false
+			}
+			if !yaml_emitter_write_indent(emitter) {
+				return false
+			}
+		}
+		if !yaml_emitter_flush(emitter) {
+			return false
+		}
+		emitter.state = yaml_EMIT_END_STATE
+		return true
+	}
+
+	return yaml_emitter_set_emitter_error(emitter, "expected DOCUMENT-START or STREAM-END")
+}
+
+// Expect the root node.
+func yaml_emitter_emit_document_content(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	emitter.states = append(emitter.states, yaml_EMIT_DOCUMENT_END_STATE)
+	return yaml_emitter_emit_node(emitter, event, true, false, false, false)
+}
+
+// Expect DOCUMENT-END.
+func yaml_emitter_emit_document_end(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	if event.typ != yaml_DOCUMENT_END_EVENT {
+		return yaml_emitter_set_emitter_error(emitter, "expected DOCUMENT-END")
+	}
+	if !yaml_emitter_write_indent(emitter) {
+		return false
+	}
+	if !event.implicit {
+		// [Go] Allocate the slice elsewhere.
+		if !yaml_emitter_write_indicator(emitter, []byte("..."), true, false, false) {
+			return false
+		}
+		if !yaml_emitter_write_indent(emitter) {
+			return false
+		}
+	}
+	if !yaml_emitter_flush(emitter) {
+		return false
+	}
+	emitter.state = yaml_EMIT_DOCUMENT_START_STATE
+	emitter.tag_directives = emitter.tag_directives[:0]
+	return true
+}
+
+// Expect a flow item node.
+func yaml_emitter_emit_flow_sequence_item(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
+	if first {
+		if !yaml_emitter_write_indicator(emitter, []byte{'['}, true, true, false) {
+			return false
+		}
+		if !yaml_emitter_increase_indent(emitter, true, false) {
+			return false
+		}
+		emitter.flow_level++
+	}
+
+	if event.typ == yaml_SEQUENCE_END_EVENT {
+		emitter.flow_level--
+		emitter.indent = emitter.indents[len(emitter.indents)-1]
+		emitter.indents = emitter.indents[:len(emitter.indents)-1]
+		if emitter.canonical && !first {
+			if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
+				return false
+			}
+			if !yaml_emitter_write_indent(emitter) {
+				return false
+			}
+		}
+		if !yaml_emitter_write_indicator(emitter, []byte{']'}, false, false, false) {
+			return false
+		}
+		emitter.state = emitter.states[len(emitter.states)-1]
+		emitter.states = emitter.states[:len(emitter.states)-1]
+
+		return true
+	}
+
+	if !first {
+		if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
+			return false
+		}
+	}
+
+	if emitter.canonical || emitter.column > emitter.best_width {
+		if !yaml_emitter_write_indent(emitter) {
+			return false
+		}
+	}
+	emitter.states = append(emitter.states, yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE)
+	return yaml_emitter_emit_node(emitter, event, false, true, false, false)
+}
+
+// Expect a flow key node.
+func yaml_emitter_emit_flow_mapping_key(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
+	if first {
+		if !yaml_emitter_write_indicator(emitter, []byte{'{'}, true, true, false) {
+			return false
+		}
+		if !yaml_emitter_increase_indent(emitter, true, false) {
+			return false
+		}
+		emitter.flow_level++
+	}
+
+	if event.typ == yaml_MAPPING_END_EVENT {
+		emitter.flow_level--
+		emitter.indent = emitter.indents[len(emitter.indents)-1]
+		emitter.indents = emitter.indents[:len(emitter.indents)-1]
+		if emitter.canonical && !first {
+			if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
+				return false
+			}
+			if !yaml_emitter_write_indent(emitter) {
+				return false
+			}
+		}
+		if !yaml_emitter_write_indicator(emitter, []byte{'}'}, false, false, false) {
+			return false
+		}
+		emitter.state = emitter.states[len(emitter.states)-1]
+		emitter.states = emitter.states[:len(emitter.states)-1]
+		return true
+	}
+
+	if !first {
+		if !yaml_emitter_write_indicator(emitter, []byte{','}, false, false, false) {
+			return false
+		}
+	}
+	if emitter.canonical || emitter.column > emitter.best_width {
+		if !yaml_emitter_write_indent(emitter) {
+			return false
+		}
+	}
+
+	if !emitter.canonical && yaml_emitter_check_simple_key(emitter) {
+		emitter.states = append(emitter.states, yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE)
+		return yaml_emitter_emit_node(emitter, event, false, false, true, true)
+	}
+	if !yaml_emitter_write_indicator(emitter, []byte{'?'}, true, false, false) {
+		return false
+	}
+	emitter.states = append(emitter.states, yaml_EMIT_FLOW_MAPPING_VALUE_STATE)
+	return yaml_emitter_emit_node(emitter, event, false, false, true, false)
+}
+
+// Expect a flow value node.
+func yaml_emitter_emit_flow_mapping_value(emitter *yaml_emitter_t, event *yaml_event_t, simple bool) bool {
+	if simple {
+		if !yaml_emitter_write_indicator(emitter, []byte{':'}, false, false, false) {
+			return false
+		}
+	} else {
+		if emitter.canonical || emitter.column > emitter.best_width {
+			if !yaml_emitter_write_indent(emitter) {
+				return false
+			}
+		}
+		if !yaml_emitter_write_indicator(emitter, []byte{':'}, true, false, false) {
+			return false
+		}
+	}
+	emitter.states = append(emitter.states, yaml_EMIT_FLOW_MAPPING_KEY_STATE)
+	return yaml_emitter_emit_node(emitter, event, false, false, true, false)
+}
+
+// Expect a block item node.
+func yaml_emitter_emit_block_sequence_item(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
+	if first {
+		if !yaml_emitter_increase_indent(emitter, false, emitter.mapping_context && !emitter.indention) {
+			return false
+		}
+	}
+	if event.typ == yaml_SEQUENCE_END_EVENT {
+		emitter.indent = emitter.indents[len(emitter.indents)-1]
+		emitter.indents = emitter.indents[:len(emitter.indents)-1]
+		emitter.state = emitter.states[len(emitter.states)-1]
+		emitter.states = emitter.states[:len(emitter.states)-1]
+		return true
+	}
+	if !yaml_emitter_write_indent(emitter) {
+		return false
+	}
+	if !yaml_emitter_write_indicator(emitter, []byte{'-'}, true, false, true) {
+		return false
+	}
+	emitter.states = append(emitter.states, yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE)
+	return yaml_emitter_emit_node(emitter, event, false, true, false, false)
+}
+
+// Expect a block key node.
+func yaml_emitter_emit_block_mapping_key(emitter *yaml_emitter_t, event *yaml_event_t, first bool) bool {
+	if first {
+		if !yaml_emitter_increase_indent(emitter, false, false) {
+			return false
+		}
+	}
+	if event.typ == yaml_MAPPING_END_EVENT {
+		emitter.indent = emitter.indents[len(emitter.indents)-1]
+		emitter.indents = emitter.indents[:len(emitter.indents)-1]
+		emitter.state = emitter.states[len(emitter.states)-1]
+		emitter.states = emitter.states[:len(emitter.states)-1]
+		return true
+	}
+	if !yaml_emitter_write_indent(emitter) {
+		return false
+	}
+	if yaml_emitter_check_simple_key(emitter) {
+		emitter.states = append(emitter.states, yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE)
+		return yaml_emitter_emit_node(emitter, event, false, false, true, true)
+	}
+	if !yaml_emitter_write_indicator(emitter, []byte{'?'}, true, false, true) {
+		return false
+	}
+	emitter.states = append(emitter.states, yaml_EMIT_BLOCK_MAPPING_VALUE_STATE)
+	return yaml_emitter_emit_node(emitter, event, false, false, true, false)
+}
+
+// Expect a block value node.
+func yaml_emitter_emit_block_mapping_value(emitter *yaml_emitter_t, event *yaml_event_t, simple bool) bool {
+	if simple {
+		if !yaml_emitter_write_indicator(emitter, []byte{':'}, false, false, false) {
+			return false
+		}
+	} else {
+		if !yaml_emitter_write_indent(emitter) {
+			return false
+		}
+		if !yaml_emitter_write_indicator(emitter, []byte{':'}, true, false, true) {
+			return false
+		}
+	}
+	emitter.states = append(emitter.states, yaml_EMIT_BLOCK_MAPPING_KEY_STATE)
+	return yaml_emitter_emit_node(emitter, event, false, false, true, false)
+}
+
+// Expect a node.
+func yaml_emitter_emit_node(emitter *yaml_emitter_t, event *yaml_event_t,
+	root bool, sequence bool, mapping bool, simple_key bool) bool {
+
+	emitter.root_context = root
+	emitter.sequence_context = sequence
+	emitter.mapping_context = mapping
+	emitter.simple_key_context = simple_key
+
+	switch event.typ {
+	case yaml_ALIAS_EVENT:
+		return yaml_emitter_emit_alias(emitter, event)
+	case yaml_SCALAR_EVENT:
+		return yaml_emitter_emit_scalar(emitter, event)
+	case yaml_SEQUENCE_START_EVENT:
+		return yaml_emitter_emit_sequence_start(emitter, event)
+	case yaml_MAPPING_START_EVENT:
+		return yaml_emitter_emit_mapping_start(emitter, event)
+	default:
+		return yaml_emitter_set_emitter_error(emitter,
+			"expected SCALAR, SEQUENCE-START, MAPPING-START, or ALIAS")
+	}
+	return false
+}
+
+// Expect ALIAS.
+func yaml_emitter_emit_alias(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	if !yaml_emitter_process_anchor(emitter) {
+		return false
+	}
+	emitter.state = emitter.states[len(emitter.states)-1]
+	emitter.states = emitter.states[:len(emitter.states)-1]
+	return true
+}
+
+// Expect SCALAR.
+func yaml_emitter_emit_scalar(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	if !yaml_emitter_select_scalar_style(emitter, event) {
+		return false
+	}
+	if !yaml_emitter_process_anchor(emitter) {
+		return false
+	}
+	if !yaml_emitter_process_tag(emitter) {
+		return false
+	}
+	if !yaml_emitter_increase_indent(emitter, true, false) {
+		return false
+	}
+	if !yaml_emitter_process_scalar(emitter) {
+		return false
+	}
+	emitter.indent = emitter.indents[len(emitter.indents)-1]
+	emitter.indents = emitter.indents[:len(emitter.indents)-1]
+	emitter.state = emitter.states[len(emitter.states)-1]
+	emitter.states = emitter.states[:len(emitter.states)-1]
+	return true
+}
+
+// Expect SEQUENCE-START.
+func yaml_emitter_emit_sequence_start(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	if !yaml_emitter_process_anchor(emitter) {
+		return false
+	}
+	if !yaml_emitter_process_tag(emitter) {
+		return false
+	}
+	if emitter.flow_level > 0 || emitter.canonical || event.sequence_style() == yaml_FLOW_SEQUENCE_STYLE ||
+		yaml_emitter_check_empty_sequence(emitter) {
+		emitter.state = yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE
+	} else {
+		emitter.state = yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE
+	}
+	return true
+}
+
+// Expect MAPPING-START.
+func yaml_emitter_emit_mapping_start(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+	if !yaml_emitter_process_anchor(emitter) {
+		return false
+	}
+	if !yaml_emitter_process_tag(emitter) {
+		return false
+	}
+	if emitter.flow_level > 0 || emitter.canonical || event.mapping_style() == yaml_FLOW_MAPPING_STYLE ||
+		yaml_emitter_check_empty_mapping(emitter) {
+		emitter.state = yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE
+	} else {
+		emitter.state = yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE
+	}
+	return true
+}
+
+// Check if the document content is an empty scalar.
+func yaml_emitter_check_empty_document(emitter *yaml_emitter_t) bool {
+	return false // [Go] Huh?
+}
+
+// Check if the next events represent an empty sequence.
+func yaml_emitter_check_empty_sequence(emitter *yaml_emitter_t) bool {
+	if len(emitter.events)-emitter.events_head < 2 {
+		return false
+	}
+	return emitter.events[emitter.events_head].typ == yaml_SEQUENCE_START_EVENT &&
+		emitter.events[emitter.events_head+1].typ == yaml_SEQUENCE_END_EVENT
+}
+
+// Check if the next events represent an empty mapping.
+func yaml_emitter_check_empty_mapping(emitter *yaml_emitter_t) bool {
+	if len(emitter.events)-emitter.events_head < 2 {
+		return false
+	}
+	return emitter.events[emitter.events_head].typ == yaml_MAPPING_START_EVENT &&
+		emitter.events[emitter.events_head+1].typ == yaml_MAPPING_END_EVENT
+}
+
+// Check if the next node can be expressed as a simple key.
+func yaml_emitter_check_simple_key(emitter *yaml_emitter_t) bool {
+	length := 0
+	switch emitter.events[emitter.events_head].typ {
+	case yaml_ALIAS_EVENT:
+		length += len(emitter.anchor_data.anchor)
+	case yaml_SCALAR_EVENT:
+		if emitter.scalar_data.multiline {
+			return false
+		}
+		length += len(emitter.anchor_data.anchor) +
+			len(emitter.tag_data.handle) +
+			len(emitter.tag_data.suffix) +
+			len(emitter.scalar_data.value)
+	case yaml_SEQUENCE_START_EVENT:
+		if !yaml_emitter_check_empty_sequence(emitter) {
+			return false
+		}
+		length += len(emitter.anchor_data.anchor) +
+			len(emitter.tag_data.handle) +
+			len(emitter.tag_data.suffix)
+	case yaml_MAPPING_START_EVENT:
+		if !yaml_emitter_check_empty_mapping(emitter) {
+			return false
+		}
+		length += len(emitter.anchor_data.anchor) +
+			len(emitter.tag_data.handle) +
+			len(emitter.tag_data.suffix)
+	default:
+		return false
+	}
+	return length <= 128
+}
+
+// Determine an acceptable scalar style.
+func yaml_emitter_select_scalar_style(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+
+	no_tag := len(emitter.tag_data.handle) == 0 && len(emitter.tag_data.suffix) == 0
+	if no_tag && !event.implicit && !event.quoted_implicit {
+		return yaml_emitter_set_emitter_error(emitter, "neither tag nor implicit flags are specified")
+	}
+
+	style := event.scalar_style()
+	if style == yaml_ANY_SCALAR_STYLE {
+		style = yaml_PLAIN_SCALAR_STYLE
+	}
+	if emitter.canonical {
+		style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+	}
+	if emitter.simple_key_context && emitter.scalar_data.multiline {
+		style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+	}
+
+	if style == yaml_PLAIN_SCALAR_STYLE {
+		if emitter.flow_level > 0 && !emitter.scalar_data.flow_plain_allowed ||
+			emitter.flow_level == 0 && !emitter.scalar_data.block_plain_allowed {
+			style = yaml_SINGLE_QUOTED_SCALAR_STYLE
+		}
+		if len(emitter.scalar_data.value) == 0 && (emitter.flow_level > 0 || emitter.simple_key_context) {
+			style = yaml_SINGLE_QUOTED_SCALAR_STYLE
+		}
+		if no_tag && !event.implicit {
+			style = yaml_SINGLE_QUOTED_SCALAR_STYLE
+		}
+	}
+	if style == yaml_SINGLE_QUOTED_SCALAR_STYLE {
+		if !emitter.scalar_data.single_quoted_allowed {
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		}
+	}
+	if style == yaml_LITERAL_SCALAR_STYLE || style == yaml_FOLDED_SCALAR_STYLE {
+		if !emitter.scalar_data.block_allowed || emitter.flow_level > 0 || emitter.simple_key_context {
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		}
+	}
+
+	if no_tag && !event.quoted_implicit && style != yaml_PLAIN_SCALAR_STYLE {
+		emitter.tag_data.handle = []byte{'!'}
+	}
+	emitter.scalar_data.style = style
+	return true
+}
+
+// Write an achor.
+func yaml_emitter_process_anchor(emitter *yaml_emitter_t) bool {
+	if emitter.anchor_data.anchor == nil {
+		return true
+	}
+	c := []byte{'&'}
+	if emitter.anchor_data.alias {
+		c[0] = '*'
+	}
+	if !yaml_emitter_write_indicator(emitter, c, true, false, false) {
+		return false
+	}
+	return yaml_emitter_write_anchor(emitter, emitter.anchor_data.anchor)
+}
+
+// Write a tag.
+func yaml_emitter_process_tag(emitter *yaml_emitter_t) bool {
+	if len(emitter.tag_data.handle) == 0 && len(emitter.tag_data.suffix) == 0 {
+		return true
+	}
+	if len(emitter.tag_data.handle) > 0 {
+		if !yaml_emitter_write_tag_handle(emitter, emitter.tag_data.handle) {
+			return false
+		}
+		if len(emitter.tag_data.suffix) > 0 {
+			if !yaml_emitter_write_tag_content(emitter, emitter.tag_data.suffix, false) {
+				return false
+			}
+		}
+	} else {
+		// [Go] Allocate these slices elsewhere.
+		if !yaml_emitter_write_indicator(emitter, []byte("!<"), true, false, false) {
+			return false
+		}
+		if !yaml_emitter_write_tag_content(emitter, emitter.tag_data.suffix, false) {
+			return false
+		}
+		if !yaml_emitter_write_indicator(emitter, []byte{'>'}, false, false, false) {
+			return false
+		}
+	}
+	return true
+}
+
+// Write a scalar.
+func yaml_emitter_process_scalar(emitter *yaml_emitter_t) bool {
+	switch emitter.scalar_data.style {
+	case yaml_PLAIN_SCALAR_STYLE:
+		return yaml_emitter_write_plain_scalar(emitter, emitter.scalar_data.value, !emitter.simple_key_context)
+
+	case yaml_SINGLE_QUOTED_SCALAR_STYLE:
+		return yaml_emitter_write_single_quoted_scalar(emitter, emitter.scalar_data.value, !emitter.simple_key_context)
+
+	case yaml_DOUBLE_QUOTED_SCALAR_STYLE:
+		return yaml_emitter_write_double_quoted_scalar(emitter, emitter.scalar_data.value, !emitter.simple_key_context)
+
+	case yaml_LITERAL_SCALAR_STYLE:
+		return yaml_emitter_write_literal_scalar(emitter, emitter.scalar_data.value)
+
+	case yaml_FOLDED_SCALAR_STYLE:
+		return yaml_emitter_write_folded_scalar(emitter, emitter.scalar_data.value)
+	}
+	panic("unknown scalar style")
+}
+
+// Check if a %YAML directive is valid.
+func yaml_emitter_analyze_version_directive(emitter *yaml_emitter_t, version_directive *yaml_version_directive_t) bool {
+	if version_directive.major != 1 || version_directive.minor != 1 {
+		return yaml_emitter_set_emitter_error(emitter, "incompatible %YAML directive")
+	}
+	return true
+}
+
+// Check if a %TAG directive is valid.
+func yaml_emitter_analyze_tag_directive(emitter *yaml_emitter_t, tag_directive *yaml_tag_directive_t) bool {
+	handle := tag_directive.handle
+	prefix := tag_directive.prefix
+	if len(handle) == 0 {
+		return yaml_emitter_set_emitter_error(emitter, "tag handle must not be empty")
+	}
+	if handle[0] != '!' {
+		return yaml_emitter_set_emitter_error(emitter, "tag handle must start with '!'")
+	}
+	if handle[len(handle)-1] != '!' {
+		return yaml_emitter_set_emitter_error(emitter, "tag handle must end with '!'")
+	}
+	for i := 1; i < len(handle)-1; i += width(handle[i]) {
+		if !is_alpha(handle, i) {
+			return yaml_emitter_set_emitter_error(emitter, "tag handle must contain alphanumerical characters only")
+		}
+	}
+	if len(prefix) == 0 {
+		return yaml_emitter_set_emitter_error(emitter, "tag prefix must not be empty")
+	}
+	return true
+}
+
+// Check if an anchor is valid.
+func yaml_emitter_analyze_anchor(emitter *yaml_emitter_t, anchor []byte, alias bool) bool {
+	if len(anchor) == 0 {
+		problem := "anchor value must not be empty"
+		if alias {
+			problem = "alias value must not be empty"
+		}
+		return yaml_emitter_set_emitter_error(emitter, problem)
+	}
+	for i := 0; i < len(anchor); i += width(anchor[i]) {
+		if !is_alpha(anchor, i) {
+			problem := "anchor value must contain alphanumerical characters only"
+			if alias {
+				problem = "alias value must contain alphanumerical characters only"
+			}
+			return yaml_emitter_set_emitter_error(emitter, problem)
+		}
+	}
+	emitter.anchor_data.anchor = anchor
+	emitter.anchor_data.alias = alias
+	return true
+}
+
+// Check if a tag is valid.
+func yaml_emitter_analyze_tag(emitter *yaml_emitter_t, tag []byte) bool {
+	if len(tag) == 0 {
+		return yaml_emitter_set_emitter_error(emitter, "tag value must not be empty")
+	}
+	for i := 0; i < len(emitter.tag_directives); i++ {
+		tag_directive := &emitter.tag_directives[i]
+		if bytes.HasPrefix(tag, tag_directive.prefix) {
+			emitter.tag_data.handle = tag_directive.handle
+			emitter.tag_data.suffix = tag[len(tag_directive.prefix):]
+			return true
+		}
+	}
+	emitter.tag_data.suffix = tag
+	return true
+}
+
+// Check if a scalar is valid.
+func yaml_emitter_analyze_scalar(emitter *yaml_emitter_t, value []byte) bool {
+	var (
+		block_indicators   = false
+		flow_indicators    = false
+		line_breaks        = false
+		special_characters = false
+
+		leading_space  = false
+		leading_break  = false
+		trailing_space = false
+		trailing_break = false
+		break_space    = false
+		space_break    = false
+
+		preceeded_by_whitespace = false
+		followed_by_whitespace  = false
+		previous_space          = false
+		previous_break          = false
+	)
+
+	emitter.scalar_data.value = value
+
+	if len(value) == 0 {
+		emitter.scalar_data.multiline = false
+		emitter.scalar_data.flow_plain_allowed = false
+		emitter.scalar_data.block_plain_allowed = true
+		emitter.scalar_data.single_quoted_allowed = true
+		emitter.scalar_data.block_allowed = false
+		return true
+	}
+
+	if len(value) >= 3 && ((value[0] == '-' && value[1] == '-' && value[2] == '-') || (value[0] == '.' && value[1] == '.' && value[2] == '.')) {
+		block_indicators = true
+		flow_indicators = true
+	}
+
+	preceeded_by_whitespace = true
+	for i, w := 0, 0; i < len(value); i += w {
+		w = width(value[i])
+		followed_by_whitespace = i+w >= len(value) || is_blank(value, i+w)
+
+		if i == 0 {
+			switch value[i] {
+			case '#', ',', '[', ']', '{', '}', '&', '*', '!', '|', '>', '\'', '"', '%', '@', '`':
+				flow_indicators = true
+				block_indicators = true
+			case '?', ':':
+				flow_indicators = true
+				if followed_by_whitespace {
+					block_indicators = true
+				}
+			case '-':
+				if followed_by_whitespace {
+					flow_indicators = true
+					block_indicators = true
+				}
+			}
+		} else {
+			switch value[i] {
+			case ',', '?', '[', ']', '{', '}':
+				flow_indicators = true
+			case ':':
+				flow_indicators = true
+				if followed_by_whitespace {
+					block_indicators = true
+				}
+			case '#':
+				if preceeded_by_whitespace {
+					flow_indicators = true
+					block_indicators = true
+				}
+			}
+		}
+
+		if !is_printable(value, i) || !is_ascii(value, i) && !emitter.unicode {
+			special_characters = true
+		}
+		if is_space(value, i) {
+			if i == 0 {
+				leading_space = true
+			}
+			if i+width(value[i]) == len(value) {
+				trailing_space = true
+			}
+			if previous_break {
+				break_space = true
+			}
+			previous_space = true
+			previous_break = false
+		} else if is_break(value, i) {
+			line_breaks = true
+			if i == 0 {
+				leading_break = true
+			}
+			if i+width(value[i]) == len(value) {
+				trailing_break = true
+			}
+			if previous_space {
+				space_break = true
+			}
+			previous_space = false
+			previous_break = true
+		} else {
+			previous_space = false
+			previous_break = false
+		}
+
+		// [Go]: Why 'z'? Couldn't be the end of the string as that's the loop condition.
+		preceeded_by_whitespace = is_blankz(value, i)
+	}
+
+	emitter.scalar_data.multiline = line_breaks
+	emitter.scalar_data.flow_plain_allowed = true
+	emitter.scalar_data.block_plain_allowed = true
+	emitter.scalar_data.single_quoted_allowed = true
+	emitter.scalar_data.block_allowed = true
+
+	if leading_space || leading_break || trailing_space || trailing_break {
+		emitter.scalar_data.flow_plain_allowed = false
+		emitter.scalar_data.block_plain_allowed = false
+	}
+	if trailing_space {
+		emitter.scalar_data.block_allowed = false
+	}
+	if break_space {
+		emitter.scalar_data.flow_plain_allowed = false
+		emitter.scalar_data.block_plain_allowed = false
+		emitter.scalar_data.single_quoted_allowed = false
+	}
+	if space_break || special_characters {
+		emitter.scalar_data.flow_plain_allowed = false
+		emitter.scalar_data.block_plain_allowed = false
+		emitter.scalar_data.single_quoted_allowed = false
+		emitter.scalar_data.block_allowed = false
+	}
+	if line_breaks {
+		emitter.scalar_data.flow_plain_allowed = false
+		emitter.scalar_data.block_plain_allowed = false
+	}
+	if flow_indicators {
+		emitter.scalar_data.flow_plain_allowed = false
+	}
+	if block_indicators {
+		emitter.scalar_data.block_plain_allowed = false
+	}
+	return true
+}
+
+// Check if the event data is valid.
+func yaml_emitter_analyze_event(emitter *yaml_emitter_t, event *yaml_event_t) bool {
+
+	emitter.anchor_data.anchor = nil
+	emitter.tag_data.handle = nil
+	emitter.tag_data.suffix = nil
+	emitter.scalar_data.value = nil
+
+	switch event.typ {
+	case yaml_ALIAS_EVENT:
+		if !yaml_emitter_analyze_anchor(emitter, event.anchor, true) {
+			return false
+		}
+
+	case yaml_SCALAR_EVENT:
+		if len(event.anchor) > 0 {
+			if !yaml_emitter_analyze_anchor(emitter, event.anchor, false) {
+				return false
+			}
+		}
+		if len(event.tag) > 0 && (emitter.canonical || (!event.implicit && !event.quoted_implicit)) {
+			if !yaml_emitter_analyze_tag(emitter, event.tag) {
+				return false
+			}
+		}
+		if !yaml_emitter_analyze_scalar(emitter, event.value) {
+			return false
+		}
+
+	case yaml_SEQUENCE_START_EVENT:
+		if len(event.anchor) > 0 {
+			if !yaml_emitter_analyze_anchor(emitter, event.anchor, false) {
+				return false
+			}
+		}
+		if len(event.tag) > 0 && (emitter.canonical || !event.implicit) {
+			if !yaml_emitter_analyze_tag(emitter, event.tag) {
+				return false
+			}
+		}
+
+	case yaml_MAPPING_START_EVENT:
+		if len(event.anchor) > 0 {
+			if !yaml_emitter_analyze_anchor(emitter, event.anchor, false) {
+				return false
+			}
+		}
+		if len(event.tag) > 0 && (emitter.canonical || !event.implicit) {
+			if !yaml_emitter_analyze_tag(emitter, event.tag) {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// Write the BOM character.
+func yaml_emitter_write_bom(emitter *yaml_emitter_t) bool {
+	if !flush(emitter) {
+		return false
+	}
+	pos := emitter.buffer_pos
+	emitter.buffer[pos+0] = '\xEF'
+	emitter.buffer[pos+1] = '\xBB'
+	emitter.buffer[pos+2] = '\xBF'
+	emitter.buffer_pos += 3
+	return true
+}
+
+func yaml_emitter_write_indent(emitter *yaml_emitter_t) bool {
+	indent := emitter.indent
+	if indent < 0 {
+		indent = 0
+	}
+	if !emitter.indention || emitter.column > indent || (emitter.column == indent && !emitter.whitespace) {
+		if !put_break(emitter) {
+			return false
+		}
+	}
+	for emitter.column < indent {
+		if !put(emitter, ' ') {
+			return false
+		}
+	}
+	emitter.whitespace = true
+	emitter.indention = true
+	return true
+}
+
+func yaml_emitter_write_indicator(emitter *yaml_emitter_t, indicator []byte, need_whitespace, is_whitespace, is_indention bool) bool {
+	if need_whitespace && !emitter.whitespace {
+		if !put(emitter, ' ') {
+			return false
+		}
+	}
+	if !write_all(emitter, indicator) {
+		return false
+	}
+	emitter.whitespace = is_whitespace
+	emitter.indention = (emitter.indention && is_indention)
+	emitter.open_ended = false
+	return true
+}
+
+func yaml_emitter_write_anchor(emitter *yaml_emitter_t, value []byte) bool {
+	if !write_all(emitter, value) {
+		return false
+	}
+	emitter.whitespace = false
+	emitter.indention = false
+	return true
+}
+
+func yaml_emitter_write_tag_handle(emitter *yaml_emitter_t, value []byte) bool {
+	if !emitter.whitespace {
+		if !put(emitter, ' ') {
+			return false
+		}
+	}
+	if !write_all(emitter, value) {
+		return false
+	}
+	emitter.whitespace = false
+	emitter.indention = false
+	return true
+}
+
+func yaml_emitter_write_tag_content(emitter *yaml_emitter_t, value []byte, need_whitespace bool) bool {
+	if need_whitespace && !emitter.whitespace {
+		if !put(emitter, ' ') {
+			return false
+		}
+	}
+	for i := 0; i < len(value); {
+		var must_write bool
+		switch value[i] {
+		case ';', '/', '?', ':', '@', '&', '=', '+', '$', ',', '_', '.', '~', '*', '\'', '(', ')', '[', ']':
+			must_write = true
+		default:
+			must_write = is_alpha(value, i)
+		}
+		if must_write {
+			if !write(emitter, value, &i) {
+				return false
+			}
+		} else {
+			w := width(value[i])
+			for k := 0; k < w; k++ {
+				octet := value[i]
+				i++
+				if !put(emitter, '%') {
+					return false
+				}
+
+				c := octet >> 4
+				if c < 10 {
+					c += '0'
+				} else {
+					c += 'A' - 10
+				}
+				if !put(emitter, c) {
+					return false
+				}
+
+				c = octet & 0x0f
+				if c < 10 {
+					c += '0'
+				} else {
+					c += 'A' - 10
+				}
+				if !put(emitter, c) {
+					return false
+				}
+			}
+		}
+	}
+	emitter.whitespace = false
+	emitter.indention = false
+	return true
+}
+
+func yaml_emitter_write_plain_scalar(emitter *yaml_emitter_t, value []byte, allow_breaks bool) bool {
+	if !emitter.whitespace {
+		if !put(emitter, ' ') {
+			return false
+		}
+	}
+
+	spaces := false
+	breaks := false
+	for i := 0; i < len(value); {
+		if is_space(value, i) {
+			if allow_breaks && !spaces && emitter.column > emitter.best_width && !is_space(value, i+1) {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+				i += width(value[i])
+			} else {
+				if !write(emitter, value, &i) {
+					return false
+				}
+			}
+			spaces = true
+		} else if is_break(value, i) {
+			if !breaks && value[i] == '\n' {
+				if !put_break(emitter) {
+					return false
+				}
+			}
+			if !write_break(emitter, value, &i) {
+				return false
+			}
+			emitter.indention = true
+			breaks = true
+		} else {
+			if breaks {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+			}
+			if !write(emitter, value, &i) {
+				return false
+			}
+			emitter.indention = false
+			spaces = false
+			breaks = false
+		}
+	}
+
+	emitter.whitespace = false
+	emitter.indention = false
+	if emitter.root_context {
+		emitter.open_ended = true
+	}
+
+	return true
+}
+
+func yaml_emitter_write_single_quoted_scalar(emitter *yaml_emitter_t, value []byte, allow_breaks bool) bool {
+
+	if !yaml_emitter_write_indicator(emitter, []byte{'\''}, true, false, false) {
+		return false
+	}
+
+	spaces := false
+	breaks := false
+	for i := 0; i < len(value); {
+		if is_space(value, i) {
+			if allow_breaks && !spaces && emitter.column > emitter.best_width && i > 0 && i < len(value)-1 && !is_space(value, i+1) {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+				i += width(value[i])
+			} else {
+				if !write(emitter, value, &i) {
+					return false
+				}
+			}
+			spaces = true
+		} else if is_break(value, i) {
+			if !breaks && value[i] == '\n' {
+				if !put_break(emitter) {
+					return false
+				}
+			}
+			if !write_break(emitter, value, &i) {
+				return false
+			}
+			emitter.indention = true
+			breaks = true
+		} else {
+			if breaks {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+			}
+			if value[i] == '\'' {
+				if !put(emitter, '\'') {
+					return false
+				}
+			}
+			if !write(emitter, value, &i) {
+				return false
+			}
+			emitter.indention = false
+			spaces = false
+			breaks = false
+		}
+	}
+	if !yaml_emitter_write_indicator(emitter, []byte{'\''}, false, false, false) {
+		return false
+	}
+	emitter.whitespace = false
+	emitter.indention = false
+	return true
+}
+
+func yaml_emitter_write_double_quoted_scalar(emitter *yaml_emitter_t, value []byte, allow_breaks bool) bool {
+	spaces := false
+	if !yaml_emitter_write_indicator(emitter, []byte{'"'}, true, false, false) {
+		return false
+	}
+
+	for i := 0; i < len(value); {
+		if !is_printable(value, i) || (!emitter.unicode && !is_ascii(value, i)) ||
+			is_bom(value, i) || is_break(value, i) ||
+			value[i] == '"' || value[i] == '\\' {
+
+			octet := value[i]
+
+			var w int
+			var v rune
+			switch {
+			case octet&0x80 == 0x00:
+				w, v = 1, rune(octet&0x7F)
+			case octet&0xE0 == 0xC0:
+				w, v = 2, rune(octet&0x1F)
+			case octet&0xF0 == 0xE0:
+				w, v = 3, rune(octet&0x0F)
+			case octet&0xF8 == 0xF0:
+				w, v = 4, rune(octet&0x07)
+			}
+			for k := 1; k < w; k++ {
+				octet = value[i+k]
+				v = (v << 6) + (rune(octet) & 0x3F)
+			}
+			i += w
+
+			if !put(emitter, '\\') {
+				return false
+			}
+
+			var ok bool
+			switch v {
+			case 0x00:
+				ok = put(emitter, '0')
+			case 0x07:
+				ok = put(emitter, 'a')
+			case 0x08:
+				ok = put(emitter, 'b')
+			case 0x09:
+				ok = put(emitter, 't')
+			case 0x0A:
+				ok = put(emitter, 'n')
+			case 0x0b:
+				ok = put(emitter, 'v')
+			case 0x0c:
+				ok = put(emitter, 'f')
+			case 0x0d:
+				ok = put(emitter, 'r')
+			case 0x1b:
+				ok = put(emitter, 'e')
+			case 0x22:
+				ok = put(emitter, '"')
+			case 0x5c:
+				ok = put(emitter, '\\')
+			case 0x85:
+				ok = put(emitter, 'N')
+			case 0xA0:
+				ok = put(emitter, '_')
+			case 0x2028:
+				ok = put(emitter, 'L')
+			case 0x2029:
+				ok = put(emitter, 'P')
+			default:
+				if v <= 0xFF {
+					ok = put(emitter, 'x')
+					w = 2
+				} else if v <= 0xFFFF {
+					ok = put(emitter, 'u')
+					w = 4
+				} else {
+					ok = put(emitter, 'U')
+					w = 8
+				}
+				for k := (w - 1) * 4; ok && k >= 0; k -= 4 {
+					digit := byte((v >> uint(k)) & 0x0F)
+					if digit < 10 {
+						ok = put(emitter, digit+'0')
+					} else {
+						ok = put(emitter, digit+'A'-10)
+					}
+				}
+			}
+			if !ok {
+				return false
+			}
+			spaces = false
+		} else if is_space(value, i) {
+			if allow_breaks && !spaces && emitter.column > emitter.best_width && i > 0 && i < len(value)-1 {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+				if is_space(value, i+1) {
+					if !put(emitter, '\\') {
+						return false
+					}
+				}
+				i += width(value[i])
+			} else if !write(emitter, value, &i) {
+				return false
+			}
+			spaces = true
+		} else {
+			if !write(emitter, value, &i) {
+				return false
+			}
+			spaces = false
+		}
+	}
+	if !yaml_emitter_write_indicator(emitter, []byte{'"'}, false, false, false) {
+		return false
+	}
+	emitter.whitespace = false
+	emitter.indention = false
+	return true
+}
+
+func yaml_emitter_write_block_scalar_hints(emitter *yaml_emitter_t, value []byte) bool {
+	if is_space(value, 0) || is_break(value, 0) {
+		indent_hint := []byte{'0' + byte(emitter.best_indent)}
+		if !yaml_emitter_write_indicator(emitter, indent_hint, false, false, false) {
+			return false
+		}
+	}
+
+	emitter.open_ended = false
+
+	var chomp_hint [1]byte
+	if len(value) == 0 {
+		chomp_hint[0] = '-'
+	} else {
+		i := len(value) - 1
+		for value[i]&0xC0 == 0x80 {
+			i--
+		}
+		if !is_break(value, i) {
+			chomp_hint[0] = '-'
+		} else if i == 0 {
+			chomp_hint[0] = '+'
+			emitter.open_ended = true
+		} else {
+			i--
+			for value[i]&0xC0 == 0x80 {
+				i--
+			}
+			if is_break(value, i) {
+				chomp_hint[0] = '+'
+				emitter.open_ended = true
+			}
+		}
+	}
+	if chomp_hint[0] != 0 {
+		if !yaml_emitter_write_indicator(emitter, chomp_hint[:], false, false, false) {
+			return false
+		}
+	}
+	return true
+}
+
+func yaml_emitter_write_literal_scalar(emitter *yaml_emitter_t, value []byte) bool {
+	if !yaml_emitter_write_indicator(emitter, []byte{'|'}, true, false, false) {
+		return false
+	}
+	if !yaml_emitter_write_block_scalar_hints(emitter, value) {
+		return false
+	}
+	if !put_break(emitter) {
+		return false
+	}
+	emitter.indention = true
+	emitter.whitespace = true
+	breaks := true
+	for i := 0; i < len(value); {
+		if is_break(value, i) {
+			if !write_break(emitter, value, &i) {
+				return false
+			}
+			emitter.indention = true
+			breaks = true
+		} else {
+			if breaks {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+			}
+			if !write(emitter, value, &i) {
+				return false
+			}
+			emitter.indention = false
+			breaks = false
+		}
+	}
+
+	return true
+}
+
+func yaml_emitter_write_folded_scalar(emitter *yaml_emitter_t, value []byte) bool {
+	if !yaml_emitter_write_indicator(emitter, []byte{'>'}, true, false, false) {
+		return false
+	}
+	if !yaml_emitter_write_block_scalar_hints(emitter, value) {
+		return false
+	}
+
+	if !put_break(emitter) {
+		return false
+	}
+	emitter.indention = true
+	emitter.whitespace = true
+
+	breaks := true
+	leading_spaces := true
+	for i := 0; i < len(value); {
+		if is_break(value, i) {
+			if !breaks && !leading_spaces && value[i] == '\n' {
+				k := 0
+				for is_break(value, k) {
+					k += width(value[k])
+				}
+				if !is_blankz(value, k) {
+					if !put_break(emitter) {
+						return false
+					}
+				}
+			}
+			if !write_break(emitter, value, &i) {
+				return false
+			}
+			emitter.indention = true
+			breaks = true
+		} else {
+			if breaks {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+				leading_spaces = is_blank(value, i)
+			}
+			if !breaks && is_space(value, i) && !is_space(value, i+1) && emitter.column > emitter.best_width {
+				if !yaml_emitter_write_indent(emitter) {
+					return false
+				}
+				i += width(value[i])
+			} else {
+				if !write(emitter, value, &i) {
+					return false
+				}
+			}
+			emitter.indention = false
+			breaks = false
+		}
+	}
+	return true
+}
diff --git a/vendor/gopkg.in/yaml.v2/encode.go b/vendor/gopkg.in/yaml.v2/encode.go
new file mode 100644
index 000000000..84f849955
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/encode.go
@@ -0,0 +1,306 @@
+package yaml
+
+import (
+	"encoding"
+	"fmt"
+	"reflect"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type encoder struct {
+	emitter yaml_emitter_t
+	event   yaml_event_t
+	out     []byte
+	flow    bool
+}
+
+func newEncoder() (e *encoder) {
+	e = &encoder{}
+	e.must(yaml_emitter_initialize(&e.emitter))
+	yaml_emitter_set_output_string(&e.emitter, &e.out)
+	yaml_emitter_set_unicode(&e.emitter, true)
+	e.must(yaml_stream_start_event_initialize(&e.event, yaml_UTF8_ENCODING))
+	e.emit()
+	e.must(yaml_document_start_event_initialize(&e.event, nil, nil, true))
+	e.emit()
+	return e
+}
+
+func (e *encoder) finish() {
+	e.must(yaml_document_end_event_initialize(&e.event, true))
+	e.emit()
+	e.emitter.open_ended = false
+	e.must(yaml_stream_end_event_initialize(&e.event))
+	e.emit()
+}
+
+func (e *encoder) destroy() {
+	yaml_emitter_delete(&e.emitter)
+}
+
+func (e *encoder) emit() {
+	// This will internally delete the e.event value.
+	if !yaml_emitter_emit(&e.emitter, &e.event) && e.event.typ != yaml_DOCUMENT_END_EVENT && e.event.typ != yaml_STREAM_END_EVENT {
+		e.must(false)
+	}
+}
+
+func (e *encoder) must(ok bool) {
+	if !ok {
+		msg := e.emitter.problem
+		if msg == "" {
+			msg = "unknown problem generating YAML content"
+		}
+		failf("%s", msg)
+	}
+}
+
+func (e *encoder) marshal(tag string, in reflect.Value) {
+	if !in.IsValid() {
+		e.nilv()
+		return
+	}
+	iface := in.Interface()
+	if m, ok := iface.(Marshaler); ok {
+		v, err := m.MarshalYAML()
+		if err != nil {
+			fail(err)
+		}
+		if v == nil {
+			e.nilv()
+			return
+		}
+		in = reflect.ValueOf(v)
+	} else if m, ok := iface.(encoding.TextMarshaler); ok {
+		text, err := m.MarshalText()
+		if err != nil {
+			fail(err)
+		}
+		in = reflect.ValueOf(string(text))
+	}
+	switch in.Kind() {
+	case reflect.Interface:
+		if in.IsNil() {
+			e.nilv()
+		} else {
+			e.marshal(tag, in.Elem())
+		}
+	case reflect.Map:
+		e.mapv(tag, in)
+	case reflect.Ptr:
+		if in.IsNil() {
+			e.nilv()
+		} else {
+			e.marshal(tag, in.Elem())
+		}
+	case reflect.Struct:
+		e.structv(tag, in)
+	case reflect.Slice:
+		if in.Type().Elem() == mapItemType {
+			e.itemsv(tag, in)
+		} else {
+			e.slicev(tag, in)
+		}
+	case reflect.String:
+		e.stringv(tag, in)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		if in.Type() == durationType {
+			e.stringv(tag, reflect.ValueOf(iface.(time.Duration).String()))
+		} else {
+			e.intv(tag, in)
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		e.uintv(tag, in)
+	case reflect.Float32, reflect.Float64:
+		e.floatv(tag, in)
+	case reflect.Bool:
+		e.boolv(tag, in)
+	default:
+		panic("cannot marshal type: " + in.Type().String())
+	}
+}
+
+func (e *encoder) mapv(tag string, in reflect.Value) {
+	e.mappingv(tag, func() {
+		keys := keyList(in.MapKeys())
+		sort.Sort(keys)
+		for _, k := range keys {
+			e.marshal("", k)
+			e.marshal("", in.MapIndex(k))
+		}
+	})
+}
+
+func (e *encoder) itemsv(tag string, in reflect.Value) {
+	e.mappingv(tag, func() {
+		slice := in.Convert(reflect.TypeOf([]MapItem{})).Interface().([]MapItem)
+		for _, item := range slice {
+			e.marshal("", reflect.ValueOf(item.Key))
+			e.marshal("", reflect.ValueOf(item.Value))
+		}
+	})
+}
+
+func (e *encoder) structv(tag string, in reflect.Value) {
+	sinfo, err := getStructInfo(in.Type())
+	if err != nil {
+		panic(err)
+	}
+	e.mappingv(tag, func() {
+		for _, info := range sinfo.FieldsList {
+			var value reflect.Value
+			if info.Inline == nil {
+				value = in.Field(info.Num)
+			} else {
+				value = in.FieldByIndex(info.Inline)
+			}
+			if info.OmitEmpty && isZero(value) {
+				continue
+			}
+			e.marshal("", reflect.ValueOf(info.Key))
+			e.flow = info.Flow
+			e.marshal("", value)
+		}
+		if sinfo.InlineMap >= 0 {
+			m := in.Field(sinfo.InlineMap)
+			if m.Len() > 0 {
+				e.flow = false
+				keys := keyList(m.MapKeys())
+				sort.Sort(keys)
+				for _, k := range keys {
+					if _, found := sinfo.FieldsMap[k.String()]; found {
+						panic(fmt.Sprintf("Can't have key %q in inlined map; conflicts with struct field", k.String()))
+					}
+					e.marshal("", k)
+					e.flow = false
+					e.marshal("", m.MapIndex(k))
+				}
+			}
+		}
+	})
+}
+
+func (e *encoder) mappingv(tag string, f func()) {
+	implicit := tag == ""
+	style := yaml_BLOCK_MAPPING_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_MAPPING_STYLE
+	}
+	e.must(yaml_mapping_start_event_initialize(&e.event, nil, []byte(tag), implicit, style))
+	e.emit()
+	f()
+	e.must(yaml_mapping_end_event_initialize(&e.event))
+	e.emit()
+}
+
+func (e *encoder) slicev(tag string, in reflect.Value) {
+	implicit := tag == ""
+	style := yaml_BLOCK_SEQUENCE_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_SEQUENCE_STYLE
+	}
+	e.must(yaml_sequence_start_event_initialize(&e.event, nil, []byte(tag), implicit, style))
+	e.emit()
+	n := in.Len()
+	for i := 0; i < n; i++ {
+		e.marshal("", in.Index(i))
+	}
+	e.must(yaml_sequence_end_event_initialize(&e.event))
+	e.emit()
+}
+
+// isBase60 returns whether s is in base 60 notation as defined in YAML 1.1.
+//
+// The base 60 float notation in YAML 1.1 is a terrible idea and is unsupported
+// in YAML 1.2 and by this package, but these should be marshalled quoted for
+// the time being for compatibility with other parsers.
+func isBase60Float(s string) (result bool) {
+	// Fast path.
+	if s == "" {
+		return false
+	}
+	c := s[0]
+	if !(c == '+' || c == '-' || c >= '0' && c <= '9') || strings.IndexByte(s, ':') < 0 {
+		return false
+	}
+	// Do the full match.
+	return base60float.MatchString(s)
+}
+
+// From http://yaml.org/type/float.html, except the regular expression there
+// is bogus. In practice parsers do not enforce the "\.[0-9_]*" suffix.
+var base60float = regexp.MustCompile(`^[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+(?:\.[0-9_]*)?$`)
+
+func (e *encoder) stringv(tag string, in reflect.Value) {
+	var style yaml_scalar_style_t
+	s := in.String()
+	rtag, rs := resolve("", s)
+	if rtag == yaml_BINARY_TAG {
+		if tag == "" || tag == yaml_STR_TAG {
+			tag = rtag
+			s = rs.(string)
+		} else if tag == yaml_BINARY_TAG {
+			failf("explicitly tagged !!binary data must be base64-encoded")
+		} else {
+			failf("cannot marshal invalid UTF-8 data as %s", shortTag(tag))
+		}
+	}
+	if tag == "" && (rtag != yaml_STR_TAG || isBase60Float(s)) {
+		style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+	} else if strings.Contains(s, "\n") {
+		style = yaml_LITERAL_SCALAR_STYLE
+	} else {
+		style = yaml_PLAIN_SCALAR_STYLE
+	}
+	e.emitScalar(s, "", tag, style)
+}
+
+func (e *encoder) boolv(tag string, in reflect.Value) {
+	var s string
+	if in.Bool() {
+		s = "true"
+	} else {
+		s = "false"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) intv(tag string, in reflect.Value) {
+	s := strconv.FormatInt(in.Int(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) uintv(tag string, in reflect.Value) {
+	s := strconv.FormatUint(in.Uint(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) floatv(tag string, in reflect.Value) {
+	// FIXME: Handle 64 bits here.
+	s := strconv.FormatFloat(float64(in.Float()), 'g', -1, 32)
+	switch s {
+	case "+Inf":
+		s = ".inf"
+	case "-Inf":
+		s = "-.inf"
+	case "NaN":
+		s = ".nan"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) nilv() {
+	e.emitScalar("null", "", "", yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) emitScalar(value, anchor, tag string, style yaml_scalar_style_t) {
+	implicit := tag == ""
+	e.must(yaml_scalar_event_initialize(&e.event, []byte(anchor), []byte(tag), []byte(value), implicit, implicit, style))
+	e.emit()
+}
diff --git a/vendor/gopkg.in/yaml.v2/parserc.go b/vendor/gopkg.in/yaml.v2/parserc.go
new file mode 100644
index 000000000..0a7037ad1
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/parserc.go
@@ -0,0 +1,1096 @@
+package yaml
+
+import (
+	"bytes"
+)
+
+// The parser implements the following grammar:
+//
+// stream               ::= STREAM-START implicit_document? explicit_document* STREAM-END
+// implicit_document    ::= block_node DOCUMENT-END*
+// explicit_document    ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
+// block_node_or_indentless_sequence    ::=
+//                          ALIAS
+//                          | properties (block_content | indentless_block_sequence)?
+//                          | block_content
+//                          | indentless_block_sequence
+// block_node           ::= ALIAS
+//                          | properties block_content?
+//                          | block_content
+// flow_node            ::= ALIAS
+//                          | properties flow_content?
+//                          | flow_content
+// properties           ::= TAG ANCHOR? | ANCHOR TAG?
+// block_content        ::= block_collection | flow_collection | SCALAR
+// flow_content         ::= flow_collection | SCALAR
+// block_collection     ::= block_sequence | block_mapping
+// flow_collection      ::= flow_sequence | flow_mapping
+// block_sequence       ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END
+// indentless_sequence  ::= (BLOCK-ENTRY block_node?)+
+// block_mapping        ::= BLOCK-MAPPING_START
+//                          ((KEY block_node_or_indentless_sequence?)?
+//                          (VALUE block_node_or_indentless_sequence?)?)*
+//                          BLOCK-END
+// flow_sequence        ::= FLOW-SEQUENCE-START
+//                          (flow_sequence_entry FLOW-ENTRY)*
+//                          flow_sequence_entry?
+//                          FLOW-SEQUENCE-END
+// flow_sequence_entry  ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+// flow_mapping         ::= FLOW-MAPPING-START
+//                          (flow_mapping_entry FLOW-ENTRY)*
+//                          flow_mapping_entry?
+//                          FLOW-MAPPING-END
+// flow_mapping_entry   ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+
+// Peek the next token in the token queue.
+func peek_token(parser *yaml_parser_t) *yaml_token_t {
+	if parser.token_available || yaml_parser_fetch_more_tokens(parser) {
+		return &parser.tokens[parser.tokens_head]
+	}
+	return nil
+}
+
+// Remove the next token from the queue (must be called after peek_token).
+func skip_token(parser *yaml_parser_t) {
+	parser.token_available = false
+	parser.tokens_parsed++
+	parser.stream_end_produced = parser.tokens[parser.tokens_head].typ == yaml_STREAM_END_TOKEN
+	parser.tokens_head++
+}
+
+// Get the next event.
+func yaml_parser_parse(parser *yaml_parser_t, event *yaml_event_t) bool {
+	// Erase the event object.
+	*event = yaml_event_t{}
+
+	// No events after the end of the stream or error.
+	if parser.stream_end_produced || parser.error != yaml_NO_ERROR || parser.state == yaml_PARSE_END_STATE {
+		return true
+	}
+
+	// Generate the next event.
+	return yaml_parser_state_machine(parser, event)
+}
+
+// Set parser error.
+func yaml_parser_set_parser_error(parser *yaml_parser_t, problem string, problem_mark yaml_mark_t) bool {
+	parser.error = yaml_PARSER_ERROR
+	parser.problem = problem
+	parser.problem_mark = problem_mark
+	return false
+}
+
+func yaml_parser_set_parser_error_context(parser *yaml_parser_t, context string, context_mark yaml_mark_t, problem string, problem_mark yaml_mark_t) bool {
+	parser.error = yaml_PARSER_ERROR
+	parser.context = context
+	parser.context_mark = context_mark
+	parser.problem = problem
+	parser.problem_mark = problem_mark
+	return false
+}
+
+// State dispatcher.
+func yaml_parser_state_machine(parser *yaml_parser_t, event *yaml_event_t) bool {
+	//trace("yaml_parser_state_machine", "state:", parser.state.String())
+
+	switch parser.state {
+	case yaml_PARSE_STREAM_START_STATE:
+		return yaml_parser_parse_stream_start(parser, event)
+
+	case yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE:
+		return yaml_parser_parse_document_start(parser, event, true)
+
+	case yaml_PARSE_DOCUMENT_START_STATE:
+		return yaml_parser_parse_document_start(parser, event, false)
+
+	case yaml_PARSE_DOCUMENT_CONTENT_STATE:
+		return yaml_parser_parse_document_content(parser, event)
+
+	case yaml_PARSE_DOCUMENT_END_STATE:
+		return yaml_parser_parse_document_end(parser, event)
+
+	case yaml_PARSE_BLOCK_NODE_STATE:
+		return yaml_parser_parse_node(parser, event, true, false)
+
+	case yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE:
+		return yaml_parser_parse_node(parser, event, true, true)
+
+	case yaml_PARSE_FLOW_NODE_STATE:
+		return yaml_parser_parse_node(parser, event, false, false)
+
+	case yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE:
+		return yaml_parser_parse_block_sequence_entry(parser, event, true)
+
+	case yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE:
+		return yaml_parser_parse_block_sequence_entry(parser, event, false)
+
+	case yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE:
+		return yaml_parser_parse_indentless_sequence_entry(parser, event)
+
+	case yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE:
+		return yaml_parser_parse_block_mapping_key(parser, event, true)
+
+	case yaml_PARSE_BLOCK_MAPPING_KEY_STATE:
+		return yaml_parser_parse_block_mapping_key(parser, event, false)
+
+	case yaml_PARSE_BLOCK_MAPPING_VALUE_STATE:
+		return yaml_parser_parse_block_mapping_value(parser, event)
+
+	case yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE:
+		return yaml_parser_parse_flow_sequence_entry(parser, event, true)
+
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE:
+		return yaml_parser_parse_flow_sequence_entry(parser, event, false)
+
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE:
+		return yaml_parser_parse_flow_sequence_entry_mapping_key(parser, event)
+
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE:
+		return yaml_parser_parse_flow_sequence_entry_mapping_value(parser, event)
+
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE:
+		return yaml_parser_parse_flow_sequence_entry_mapping_end(parser, event)
+
+	case yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE:
+		return yaml_parser_parse_flow_mapping_key(parser, event, true)
+
+	case yaml_PARSE_FLOW_MAPPING_KEY_STATE:
+		return yaml_parser_parse_flow_mapping_key(parser, event, false)
+
+	case yaml_PARSE_FLOW_MAPPING_VALUE_STATE:
+		return yaml_parser_parse_flow_mapping_value(parser, event, false)
+
+	case yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE:
+		return yaml_parser_parse_flow_mapping_value(parser, event, true)
+
+	default:
+		panic("invalid parser state")
+	}
+	return false
+}
+
+// Parse the production:
+// stream   ::= STREAM-START implicit_document? explicit_document* STREAM-END
+//              ************
+func yaml_parser_parse_stream_start(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	if token.typ != yaml_STREAM_START_TOKEN {
+		return yaml_parser_set_parser_error(parser, "did not find expected <stream-start>", token.start_mark)
+	}
+	parser.state = yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE
+	*event = yaml_event_t{
+		typ:        yaml_STREAM_START_EVENT,
+		start_mark: token.start_mark,
+		end_mark:   token.end_mark,
+		encoding:   token.encoding,
+	}
+	skip_token(parser)
+	return true
+}
+
+// Parse the productions:
+// implicit_document    ::= block_node DOCUMENT-END*
+//                          *
+// explicit_document    ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
+//                          *************************
+func yaml_parser_parse_document_start(parser *yaml_parser_t, event *yaml_event_t, implicit bool) bool {
+
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	// Parse extra document end indicators.
+	if !implicit {
+		for token.typ == yaml_DOCUMENT_END_TOKEN {
+			skip_token(parser)
+			token = peek_token(parser)
+			if token == nil {
+				return false
+			}
+		}
+	}
+
+	if implicit && token.typ != yaml_VERSION_DIRECTIVE_TOKEN &&
+		token.typ != yaml_TAG_DIRECTIVE_TOKEN &&
+		token.typ != yaml_DOCUMENT_START_TOKEN &&
+		token.typ != yaml_STREAM_END_TOKEN {
+		// Parse an implicit document.
+		if !yaml_parser_process_directives(parser, nil, nil) {
+			return false
+		}
+		parser.states = append(parser.states, yaml_PARSE_DOCUMENT_END_STATE)
+		parser.state = yaml_PARSE_BLOCK_NODE_STATE
+
+		*event = yaml_event_t{
+			typ:        yaml_DOCUMENT_START_EVENT,
+			start_mark: token.start_mark,
+			end_mark:   token.end_mark,
+		}
+
+	} else if token.typ != yaml_STREAM_END_TOKEN {
+		// Parse an explicit document.
+		var version_directive *yaml_version_directive_t
+		var tag_directives []yaml_tag_directive_t
+		start_mark := token.start_mark
+		if !yaml_parser_process_directives(parser, &version_directive, &tag_directives) {
+			return false
+		}
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ != yaml_DOCUMENT_START_TOKEN {
+			yaml_parser_set_parser_error(parser,
+				"did not find expected <document start>", token.start_mark)
+			return false
+		}
+		parser.states = append(parser.states, yaml_PARSE_DOCUMENT_END_STATE)
+		parser.state = yaml_PARSE_DOCUMENT_CONTENT_STATE
+		end_mark := token.end_mark
+
+		*event = yaml_event_t{
+			typ:               yaml_DOCUMENT_START_EVENT,
+			start_mark:        start_mark,
+			end_mark:          end_mark,
+			version_directive: version_directive,
+			tag_directives:    tag_directives,
+			implicit:          false,
+		}
+		skip_token(parser)
+
+	} else {
+		// Parse the stream end.
+		parser.state = yaml_PARSE_END_STATE
+		*event = yaml_event_t{
+			typ:        yaml_STREAM_END_EVENT,
+			start_mark: token.start_mark,
+			end_mark:   token.end_mark,
+		}
+		skip_token(parser)
+	}
+
+	return true
+}
+
+// Parse the productions:
+// explicit_document    ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
+//                                                    ***********
+//
+func yaml_parser_parse_document_content(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	if token.typ == yaml_VERSION_DIRECTIVE_TOKEN ||
+		token.typ == yaml_TAG_DIRECTIVE_TOKEN ||
+		token.typ == yaml_DOCUMENT_START_TOKEN ||
+		token.typ == yaml_DOCUMENT_END_TOKEN ||
+		token.typ == yaml_STREAM_END_TOKEN {
+		parser.state = parser.states[len(parser.states)-1]
+		parser.states = parser.states[:len(parser.states)-1]
+		return yaml_parser_process_empty_scalar(parser, event,
+			token.start_mark)
+	}
+	return yaml_parser_parse_node(parser, event, true, false)
+}
+
+// Parse the productions:
+// implicit_document    ::= block_node DOCUMENT-END*
+//                                     *************
+// explicit_document    ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
+//
+func yaml_parser_parse_document_end(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	start_mark := token.start_mark
+	end_mark := token.start_mark
+
+	implicit := true
+	if token.typ == yaml_DOCUMENT_END_TOKEN {
+		end_mark = token.end_mark
+		skip_token(parser)
+		implicit = false
+	}
+
+	parser.tag_directives = parser.tag_directives[:0]
+
+	parser.state = yaml_PARSE_DOCUMENT_START_STATE
+	*event = yaml_event_t{
+		typ:        yaml_DOCUMENT_END_EVENT,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+		implicit:   implicit,
+	}
+	return true
+}
+
+// Parse the productions:
+// block_node_or_indentless_sequence    ::=
+//                          ALIAS
+//                          *****
+//                          | properties (block_content | indentless_block_sequence)?
+//                            **********  *
+//                          | block_content | indentless_block_sequence
+//                            *
+// block_node           ::= ALIAS
+//                          *****
+//                          | properties block_content?
+//                            ********** *
+//                          | block_content
+//                            *
+// flow_node            ::= ALIAS
+//                          *****
+//                          | properties flow_content?
+//                            ********** *
+//                          | flow_content
+//                            *
+// properties           ::= TAG ANCHOR? | ANCHOR TAG?
+//                          *************************
+// block_content        ::= block_collection | flow_collection | SCALAR
+//                                                               ******
+// flow_content         ::= flow_collection | SCALAR
+//                                            ******
+func yaml_parser_parse_node(parser *yaml_parser_t, event *yaml_event_t, block, indentless_sequence bool) bool {
+	//defer trace("yaml_parser_parse_node", "block:", block, "indentless_sequence:", indentless_sequence)()
+
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	if token.typ == yaml_ALIAS_TOKEN {
+		parser.state = parser.states[len(parser.states)-1]
+		parser.states = parser.states[:len(parser.states)-1]
+		*event = yaml_event_t{
+			typ:        yaml_ALIAS_EVENT,
+			start_mark: token.start_mark,
+			end_mark:   token.end_mark,
+			anchor:     token.value,
+		}
+		skip_token(parser)
+		return true
+	}
+
+	start_mark := token.start_mark
+	end_mark := token.start_mark
+
+	var tag_token bool
+	var tag_handle, tag_suffix, anchor []byte
+	var tag_mark yaml_mark_t
+	if token.typ == yaml_ANCHOR_TOKEN {
+		anchor = token.value
+		start_mark = token.start_mark
+		end_mark = token.end_mark
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ == yaml_TAG_TOKEN {
+			tag_token = true
+			tag_handle = token.value
+			tag_suffix = token.suffix
+			tag_mark = token.start_mark
+			end_mark = token.end_mark
+			skip_token(parser)
+			token = peek_token(parser)
+			if token == nil {
+				return false
+			}
+		}
+	} else if token.typ == yaml_TAG_TOKEN {
+		tag_token = true
+		tag_handle = token.value
+		tag_suffix = token.suffix
+		start_mark = token.start_mark
+		tag_mark = token.start_mark
+		end_mark = token.end_mark
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ == yaml_ANCHOR_TOKEN {
+			anchor = token.value
+			end_mark = token.end_mark
+			skip_token(parser)
+			token = peek_token(parser)
+			if token == nil {
+				return false
+			}
+		}
+	}
+
+	var tag []byte
+	if tag_token {
+		if len(tag_handle) == 0 {
+			tag = tag_suffix
+			tag_suffix = nil
+		} else {
+			for i := range parser.tag_directives {
+				if bytes.Equal(parser.tag_directives[i].handle, tag_handle) {
+					tag = append([]byte(nil), parser.tag_directives[i].prefix...)
+					tag = append(tag, tag_suffix...)
+					break
+				}
+			}
+			if len(tag) == 0 {
+				yaml_parser_set_parser_error_context(parser,
+					"while parsing a node", start_mark,
+					"found undefined tag handle", tag_mark)
+				return false
+			}
+		}
+	}
+
+	implicit := len(tag) == 0
+	if indentless_sequence && token.typ == yaml_BLOCK_ENTRY_TOKEN {
+		end_mark = token.end_mark
+		parser.state = yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE
+		*event = yaml_event_t{
+			typ:        yaml_SEQUENCE_START_EVENT,
+			start_mark: start_mark,
+			end_mark:   end_mark,
+			anchor:     anchor,
+			tag:        tag,
+			implicit:   implicit,
+			style:      yaml_style_t(yaml_BLOCK_SEQUENCE_STYLE),
+		}
+		return true
+	}
+	if token.typ == yaml_SCALAR_TOKEN {
+		var plain_implicit, quoted_implicit bool
+		end_mark = token.end_mark
+		if (len(tag) == 0 && token.style == yaml_PLAIN_SCALAR_STYLE) || (len(tag) == 1 && tag[0] == '!') {
+			plain_implicit = true
+		} else if len(tag) == 0 {
+			quoted_implicit = true
+		}
+		parser.state = parser.states[len(parser.states)-1]
+		parser.states = parser.states[:len(parser.states)-1]
+
+		*event = yaml_event_t{
+			typ:             yaml_SCALAR_EVENT,
+			start_mark:      start_mark,
+			end_mark:        end_mark,
+			anchor:          anchor,
+			tag:             tag,
+			value:           token.value,
+			implicit:        plain_implicit,
+			quoted_implicit: quoted_implicit,
+			style:           yaml_style_t(token.style),
+		}
+		skip_token(parser)
+		return true
+	}
+	if token.typ == yaml_FLOW_SEQUENCE_START_TOKEN {
+		// [Go] Some of the events below can be merged as they differ only on style.
+		end_mark = token.end_mark
+		parser.state = yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE
+		*event = yaml_event_t{
+			typ:        yaml_SEQUENCE_START_EVENT,
+			start_mark: start_mark,
+			end_mark:   end_mark,
+			anchor:     anchor,
+			tag:        tag,
+			implicit:   implicit,
+			style:      yaml_style_t(yaml_FLOW_SEQUENCE_STYLE),
+		}
+		return true
+	}
+	if token.typ == yaml_FLOW_MAPPING_START_TOKEN {
+		end_mark = token.end_mark
+		parser.state = yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE
+		*event = yaml_event_t{
+			typ:        yaml_MAPPING_START_EVENT,
+			start_mark: start_mark,
+			end_mark:   end_mark,
+			anchor:     anchor,
+			tag:        tag,
+			implicit:   implicit,
+			style:      yaml_style_t(yaml_FLOW_MAPPING_STYLE),
+		}
+		return true
+	}
+	if block && token.typ == yaml_BLOCK_SEQUENCE_START_TOKEN {
+		end_mark = token.end_mark
+		parser.state = yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE
+		*event = yaml_event_t{
+			typ:        yaml_SEQUENCE_START_EVENT,
+			start_mark: start_mark,
+			end_mark:   end_mark,
+			anchor:     anchor,
+			tag:        tag,
+			implicit:   implicit,
+			style:      yaml_style_t(yaml_BLOCK_SEQUENCE_STYLE),
+		}
+		return true
+	}
+	if block && token.typ == yaml_BLOCK_MAPPING_START_TOKEN {
+		end_mark = token.end_mark
+		parser.state = yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE
+		*event = yaml_event_t{
+			typ:        yaml_MAPPING_START_EVENT,
+			start_mark: start_mark,
+			end_mark:   end_mark,
+			anchor:     anchor,
+			tag:        tag,
+			implicit:   implicit,
+			style:      yaml_style_t(yaml_BLOCK_MAPPING_STYLE),
+		}
+		return true
+	}
+	if len(anchor) > 0 || len(tag) > 0 {
+		parser.state = parser.states[len(parser.states)-1]
+		parser.states = parser.states[:len(parser.states)-1]
+
+		*event = yaml_event_t{
+			typ:             yaml_SCALAR_EVENT,
+			start_mark:      start_mark,
+			end_mark:        end_mark,
+			anchor:          anchor,
+			tag:             tag,
+			implicit:        implicit,
+			quoted_implicit: false,
+			style:           yaml_style_t(yaml_PLAIN_SCALAR_STYLE),
+		}
+		return true
+	}
+
+	context := "while parsing a flow node"
+	if block {
+		context = "while parsing a block node"
+	}
+	yaml_parser_set_parser_error_context(parser, context, start_mark,
+		"did not find expected node content", token.start_mark)
+	return false
+}
+
+// Parse the productions:
+// block_sequence ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END
+//                    ********************  *********** *             *********
+//
+func yaml_parser_parse_block_sequence_entry(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
+	if first {
+		token := peek_token(parser)
+		parser.marks = append(parser.marks, token.start_mark)
+		skip_token(parser)
+	}
+
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	if token.typ == yaml_BLOCK_ENTRY_TOKEN {
+		mark := token.end_mark
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ != yaml_BLOCK_ENTRY_TOKEN && token.typ != yaml_BLOCK_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE)
+			return yaml_parser_parse_node(parser, event, true, false)
+		} else {
+			parser.state = yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE
+			return yaml_parser_process_empty_scalar(parser, event, mark)
+		}
+	}
+	if token.typ == yaml_BLOCK_END_TOKEN {
+		parser.state = parser.states[len(parser.states)-1]
+		parser.states = parser.states[:len(parser.states)-1]
+		parser.marks = parser.marks[:len(parser.marks)-1]
+
+		*event = yaml_event_t{
+			typ:        yaml_SEQUENCE_END_EVENT,
+			start_mark: token.start_mark,
+			end_mark:   token.end_mark,
+		}
+
+		skip_token(parser)
+		return true
+	}
+
+	context_mark := parser.marks[len(parser.marks)-1]
+	parser.marks = parser.marks[:len(parser.marks)-1]
+	return yaml_parser_set_parser_error_context(parser,
+		"while parsing a block collection", context_mark,
+		"did not find expected '-' indicator", token.start_mark)
+}
+
+// Parse the productions:
+// indentless_sequence  ::= (BLOCK-ENTRY block_node?)+
+//                           *********** *
+func yaml_parser_parse_indentless_sequence_entry(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	if token.typ == yaml_BLOCK_ENTRY_TOKEN {
+		mark := token.end_mark
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ != yaml_BLOCK_ENTRY_TOKEN &&
+			token.typ != yaml_KEY_TOKEN &&
+			token.typ != yaml_VALUE_TOKEN &&
+			token.typ != yaml_BLOCK_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE)
+			return yaml_parser_parse_node(parser, event, true, false)
+		}
+		parser.state = yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE
+		return yaml_parser_process_empty_scalar(parser, event, mark)
+	}
+	parser.state = parser.states[len(parser.states)-1]
+	parser.states = parser.states[:len(parser.states)-1]
+
+	*event = yaml_event_t{
+		typ:        yaml_SEQUENCE_END_EVENT,
+		start_mark: token.start_mark,
+		end_mark:   token.start_mark, // [Go] Shouldn't this be token.end_mark?
+	}
+	return true
+}
+
+// Parse the productions:
+// block_mapping        ::= BLOCK-MAPPING_START
+//                          *******************
+//                          ((KEY block_node_or_indentless_sequence?)?
+//                            *** *
+//                          (VALUE block_node_or_indentless_sequence?)?)*
+//
+//                          BLOCK-END
+//                          *********
+//
+func yaml_parser_parse_block_mapping_key(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
+	if first {
+		token := peek_token(parser)
+		parser.marks = append(parser.marks, token.start_mark)
+		skip_token(parser)
+	}
+
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	if token.typ == yaml_KEY_TOKEN {
+		mark := token.end_mark
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ != yaml_KEY_TOKEN &&
+			token.typ != yaml_VALUE_TOKEN &&
+			token.typ != yaml_BLOCK_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_BLOCK_MAPPING_VALUE_STATE)
+			return yaml_parser_parse_node(parser, event, true, true)
+		} else {
+			parser.state = yaml_PARSE_BLOCK_MAPPING_VALUE_STATE
+			return yaml_parser_process_empty_scalar(parser, event, mark)
+		}
+	} else if token.typ == yaml_BLOCK_END_TOKEN {
+		parser.state = parser.states[len(parser.states)-1]
+		parser.states = parser.states[:len(parser.states)-1]
+		parser.marks = parser.marks[:len(parser.marks)-1]
+		*event = yaml_event_t{
+			typ:        yaml_MAPPING_END_EVENT,
+			start_mark: token.start_mark,
+			end_mark:   token.end_mark,
+		}
+		skip_token(parser)
+		return true
+	}
+
+	context_mark := parser.marks[len(parser.marks)-1]
+	parser.marks = parser.marks[:len(parser.marks)-1]
+	return yaml_parser_set_parser_error_context(parser,
+		"while parsing a block mapping", context_mark,
+		"did not find expected key", token.start_mark)
+}
+
+// Parse the productions:
+// block_mapping        ::= BLOCK-MAPPING_START
+//
+//                          ((KEY block_node_or_indentless_sequence?)?
+//
+//                          (VALUE block_node_or_indentless_sequence?)?)*
+//                           ***** *
+//                          BLOCK-END
+//
+//
+func yaml_parser_parse_block_mapping_value(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	if token.typ == yaml_VALUE_TOKEN {
+		mark := token.end_mark
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ != yaml_KEY_TOKEN &&
+			token.typ != yaml_VALUE_TOKEN &&
+			token.typ != yaml_BLOCK_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_BLOCK_MAPPING_KEY_STATE)
+			return yaml_parser_parse_node(parser, event, true, true)
+		}
+		parser.state = yaml_PARSE_BLOCK_MAPPING_KEY_STATE
+		return yaml_parser_process_empty_scalar(parser, event, mark)
+	}
+	parser.state = yaml_PARSE_BLOCK_MAPPING_KEY_STATE
+	return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
+}
+
+// Parse the productions:
+// flow_sequence        ::= FLOW-SEQUENCE-START
+//                          *******************
+//                          (flow_sequence_entry FLOW-ENTRY)*
+//                           *                   **********
+//                          flow_sequence_entry?
+//                          *
+//                          FLOW-SEQUENCE-END
+//                          *****************
+// flow_sequence_entry  ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+//                          *
+//
+func yaml_parser_parse_flow_sequence_entry(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
+	if first {
+		token := peek_token(parser)
+		parser.marks = append(parser.marks, token.start_mark)
+		skip_token(parser)
+	}
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	if token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
+		if !first {
+			if token.typ == yaml_FLOW_ENTRY_TOKEN {
+				skip_token(parser)
+				token = peek_token(parser)
+				if token == nil {
+					return false
+				}
+			} else {
+				context_mark := parser.marks[len(parser.marks)-1]
+				parser.marks = parser.marks[:len(parser.marks)-1]
+				return yaml_parser_set_parser_error_context(parser,
+					"while parsing a flow sequence", context_mark,
+					"did not find expected ',' or ']'", token.start_mark)
+			}
+		}
+
+		if token.typ == yaml_KEY_TOKEN {
+			parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE
+			*event = yaml_event_t{
+				typ:        yaml_MAPPING_START_EVENT,
+				start_mark: token.start_mark,
+				end_mark:   token.end_mark,
+				implicit:   true,
+				style:      yaml_style_t(yaml_FLOW_MAPPING_STYLE),
+			}
+			skip_token(parser)
+			return true
+		} else if token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE)
+			return yaml_parser_parse_node(parser, event, false, false)
+		}
+	}
+
+	parser.state = parser.states[len(parser.states)-1]
+	parser.states = parser.states[:len(parser.states)-1]
+	parser.marks = parser.marks[:len(parser.marks)-1]
+
+	*event = yaml_event_t{
+		typ:        yaml_SEQUENCE_END_EVENT,
+		start_mark: token.start_mark,
+		end_mark:   token.end_mark,
+	}
+
+	skip_token(parser)
+	return true
+}
+
+//
+// Parse the productions:
+// flow_sequence_entry  ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+//                                      *** *
+//
+func yaml_parser_parse_flow_sequence_entry_mapping_key(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	if token.typ != yaml_VALUE_TOKEN &&
+		token.typ != yaml_FLOW_ENTRY_TOKEN &&
+		token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
+		parser.states = append(parser.states, yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE)
+		return yaml_parser_parse_node(parser, event, false, false)
+	}
+	mark := token.end_mark
+	skip_token(parser)
+	parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE
+	return yaml_parser_process_empty_scalar(parser, event, mark)
+}
+
+// Parse the productions:
+// flow_sequence_entry  ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+//                                                      ***** *
+//
+func yaml_parser_parse_flow_sequence_entry_mapping_value(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	if token.typ == yaml_VALUE_TOKEN {
+		skip_token(parser)
+		token := peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ != yaml_FLOW_ENTRY_TOKEN && token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE)
+			return yaml_parser_parse_node(parser, event, false, false)
+		}
+	}
+	parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE
+	return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
+}
+
+// Parse the productions:
+// flow_sequence_entry  ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+//                                                                      *
+//
+func yaml_parser_parse_flow_sequence_entry_mapping_end(parser *yaml_parser_t, event *yaml_event_t) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE
+	*event = yaml_event_t{
+		typ:        yaml_MAPPING_END_EVENT,
+		start_mark: token.start_mark,
+		end_mark:   token.start_mark, // [Go] Shouldn't this be end_mark?
+	}
+	return true
+}
+
+// Parse the productions:
+// flow_mapping         ::= FLOW-MAPPING-START
+//                          ******************
+//                          (flow_mapping_entry FLOW-ENTRY)*
+//                           *                  **********
+//                          flow_mapping_entry?
+//                          ******************
+//                          FLOW-MAPPING-END
+//                          ****************
+// flow_mapping_entry   ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+//                          *           *** *
+//
+func yaml_parser_parse_flow_mapping_key(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
+	if first {
+		token := peek_token(parser)
+		parser.marks = append(parser.marks, token.start_mark)
+		skip_token(parser)
+	}
+
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	if token.typ != yaml_FLOW_MAPPING_END_TOKEN {
+		if !first {
+			if token.typ == yaml_FLOW_ENTRY_TOKEN {
+				skip_token(parser)
+				token = peek_token(parser)
+				if token == nil {
+					return false
+				}
+			} else {
+				context_mark := parser.marks[len(parser.marks)-1]
+				parser.marks = parser.marks[:len(parser.marks)-1]
+				return yaml_parser_set_parser_error_context(parser,
+					"while parsing a flow mapping", context_mark,
+					"did not find expected ',' or '}'", token.start_mark)
+			}
+		}
+
+		if token.typ == yaml_KEY_TOKEN {
+			skip_token(parser)
+			token = peek_token(parser)
+			if token == nil {
+				return false
+			}
+			if token.typ != yaml_VALUE_TOKEN &&
+				token.typ != yaml_FLOW_ENTRY_TOKEN &&
+				token.typ != yaml_FLOW_MAPPING_END_TOKEN {
+				parser.states = append(parser.states, yaml_PARSE_FLOW_MAPPING_VALUE_STATE)
+				return yaml_parser_parse_node(parser, event, false, false)
+			} else {
+				parser.state = yaml_PARSE_FLOW_MAPPING_VALUE_STATE
+				return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
+			}
+		} else if token.typ != yaml_FLOW_MAPPING_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE)
+			return yaml_parser_parse_node(parser, event, false, false)
+		}
+	}
+
+	parser.state = parser.states[len(parser.states)-1]
+	parser.states = parser.states[:len(parser.states)-1]
+	parser.marks = parser.marks[:len(parser.marks)-1]
+	*event = yaml_event_t{
+		typ:        yaml_MAPPING_END_EVENT,
+		start_mark: token.start_mark,
+		end_mark:   token.end_mark,
+	}
+	skip_token(parser)
+	return true
+}
+
+// Parse the productions:
+// flow_mapping_entry   ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+//                                   *                  ***** *
+//
+func yaml_parser_parse_flow_mapping_value(parser *yaml_parser_t, event *yaml_event_t, empty bool) bool {
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+	if empty {
+		parser.state = yaml_PARSE_FLOW_MAPPING_KEY_STATE
+		return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
+	}
+	if token.typ == yaml_VALUE_TOKEN {
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+		if token.typ != yaml_FLOW_ENTRY_TOKEN && token.typ != yaml_FLOW_MAPPING_END_TOKEN {
+			parser.states = append(parser.states, yaml_PARSE_FLOW_MAPPING_KEY_STATE)
+			return yaml_parser_parse_node(parser, event, false, false)
+		}
+	}
+	parser.state = yaml_PARSE_FLOW_MAPPING_KEY_STATE
+	return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
+}
+
+// Generate an empty scalar event.
+func yaml_parser_process_empty_scalar(parser *yaml_parser_t, event *yaml_event_t, mark yaml_mark_t) bool {
+	*event = yaml_event_t{
+		typ:        yaml_SCALAR_EVENT,
+		start_mark: mark,
+		end_mark:   mark,
+		value:      nil, // Empty
+		implicit:   true,
+		style:      yaml_style_t(yaml_PLAIN_SCALAR_STYLE),
+	}
+	return true
+}
+
+var default_tag_directives = []yaml_tag_directive_t{
+	{[]byte("!"), []byte("!")},
+	{[]byte("!!"), []byte("tag:yaml.org,2002:")},
+}
+
+// Parse directives.
+func yaml_parser_process_directives(parser *yaml_parser_t,
+	version_directive_ref **yaml_version_directive_t,
+	tag_directives_ref *[]yaml_tag_directive_t) bool {
+
+	var version_directive *yaml_version_directive_t
+	var tag_directives []yaml_tag_directive_t
+
+	token := peek_token(parser)
+	if token == nil {
+		return false
+	}
+
+	for token.typ == yaml_VERSION_DIRECTIVE_TOKEN || token.typ == yaml_TAG_DIRECTIVE_TOKEN {
+		if token.typ == yaml_VERSION_DIRECTIVE_TOKEN {
+			if version_directive != nil {
+				yaml_parser_set_parser_error(parser,
+					"found duplicate %YAML directive", token.start_mark)
+				return false
+			}
+			if token.major != 1 || token.minor != 1 {
+				yaml_parser_set_parser_error(parser,
+					"found incompatible YAML document", token.start_mark)
+				return false
+			}
+			version_directive = &yaml_version_directive_t{
+				major: token.major,
+				minor: token.minor,
+			}
+		} else if token.typ == yaml_TAG_DIRECTIVE_TOKEN {
+			value := yaml_tag_directive_t{
+				handle: token.value,
+				prefix: token.prefix,
+			}
+			if !yaml_parser_append_tag_directive(parser, value, false, token.start_mark) {
+				return false
+			}
+			tag_directives = append(tag_directives, value)
+		}
+
+		skip_token(parser)
+		token = peek_token(parser)
+		if token == nil {
+			return false
+		}
+	}
+
+	for i := range default_tag_directives {
+		if !yaml_parser_append_tag_directive(parser, default_tag_directives[i], true, token.start_mark) {
+			return false
+		}
+	}
+
+	if version_directive_ref != nil {
+		*version_directive_ref = version_directive
+	}
+	if tag_directives_ref != nil {
+		*tag_directives_ref = tag_directives
+	}
+	return true
+}
+
+// Append a tag directive to the directives stack.
+func yaml_parser_append_tag_directive(parser *yaml_parser_t, value yaml_tag_directive_t, allow_duplicates bool, mark yaml_mark_t) bool {
+	for i := range parser.tag_directives {
+		if bytes.Equal(value.handle, parser.tag_directives[i].handle) {
+			if allow_duplicates {
+				return true
+			}
+			return yaml_parser_set_parser_error(parser, "found duplicate %TAG directive", mark)
+		}
+	}
+
+	// [Go] I suspect the copy is unnecessary. This was likely done
+	// because there was no way to track ownership of the data.
+	value_copy := yaml_tag_directive_t{
+		handle: make([]byte, len(value.handle)),
+		prefix: make([]byte, len(value.prefix)),
+	}
+	copy(value_copy.handle, value.handle)
+	copy(value_copy.prefix, value.prefix)
+	parser.tag_directives = append(parser.tag_directives, value_copy)
+	return true
+}
diff --git a/vendor/gopkg.in/yaml.v2/readerc.go b/vendor/gopkg.in/yaml.v2/readerc.go
new file mode 100644
index 000000000..f45079171
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/readerc.go
@@ -0,0 +1,394 @@
+package yaml
+
+import (
+	"io"
+)
+
+// Set the reader error and return 0.
+func yaml_parser_set_reader_error(parser *yaml_parser_t, problem string, offset int, value int) bool {
+	parser.error = yaml_READER_ERROR
+	parser.problem = problem
+	parser.problem_offset = offset
+	parser.problem_value = value
+	return false
+}
+
+// Byte order marks.
+const (
+	bom_UTF8    = "\xef\xbb\xbf"
+	bom_UTF16LE = "\xff\xfe"
+	bom_UTF16BE = "\xfe\xff"
+)
+
+// Determine the input stream encoding by checking the BOM symbol. If no BOM is
+// found, the UTF-8 encoding is assumed. Return 1 on success, 0 on failure.
+func yaml_parser_determine_encoding(parser *yaml_parser_t) bool {
+	// Ensure that we had enough bytes in the raw buffer.
+	for !parser.eof && len(parser.raw_buffer)-parser.raw_buffer_pos < 3 {
+		if !yaml_parser_update_raw_buffer(parser) {
+			return false
+		}
+	}
+
+	// Determine the encoding.
+	buf := parser.raw_buffer
+	pos := parser.raw_buffer_pos
+	avail := len(buf) - pos
+	if avail >= 2 && buf[pos] == bom_UTF16LE[0] && buf[pos+1] == bom_UTF16LE[1] {
+		parser.encoding = yaml_UTF16LE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 2 && buf[pos] == bom_UTF16BE[0] && buf[pos+1] == bom_UTF16BE[1] {
+		parser.encoding = yaml_UTF16BE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 3 && buf[pos] == bom_UTF8[0] && buf[pos+1] == bom_UTF8[1] && buf[pos+2] == bom_UTF8[2] {
+		parser.encoding = yaml_UTF8_ENCODING
+		parser.raw_buffer_pos += 3
+		parser.offset += 3
+	} else {
+		parser.encoding = yaml_UTF8_ENCODING
+	}
+	return true
+}
+
+// Update the raw buffer.
+func yaml_parser_update_raw_buffer(parser *yaml_parser_t) bool {
+	size_read := 0
+
+	// Return if the raw buffer is full.
+	if parser.raw_buffer_pos == 0 && len(parser.raw_buffer) == cap(parser.raw_buffer) {
+		return true
+	}
+
+	// Return on EOF.
+	if parser.eof {
+		return true
+	}
+
+	// Move the remaining bytes in the raw buffer to the beginning.
+	if parser.raw_buffer_pos > 0 && parser.raw_buffer_pos < len(parser.raw_buffer) {
+		copy(parser.raw_buffer, parser.raw_buffer[parser.raw_buffer_pos:])
+	}
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)-parser.raw_buffer_pos]
+	parser.raw_buffer_pos = 0
+
+	// Call the read handler to fill the buffer.
+	size_read, err := parser.read_handler(parser, parser.raw_buffer[len(parser.raw_buffer):cap(parser.raw_buffer)])
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)+size_read]
+	if err == io.EOF {
+		parser.eof = true
+	} else if err != nil {
+		return yaml_parser_set_reader_error(parser, "input error: "+err.Error(), parser.offset, -1)
+	}
+	return true
+}
+
+// Ensure that the buffer contains at least `length` characters.
+// Return true on success, false on failure.
+//
+// The length is supposed to be significantly less that the buffer size.
+func yaml_parser_update_buffer(parser *yaml_parser_t, length int) bool {
+	if parser.read_handler == nil {
+		panic("read handler must be set")
+	}
+
+	// If the EOF flag is set and the raw buffer is empty, do nothing.
+	if parser.eof && parser.raw_buffer_pos == len(parser.raw_buffer) {
+		return true
+	}
+
+	// Return if the buffer contains enough characters.
+	if parser.unread >= length {
+		return true
+	}
+
+	// Determine the input encoding if it is not known yet.
+	if parser.encoding == yaml_ANY_ENCODING {
+		if !yaml_parser_determine_encoding(parser) {
+			return false
+		}
+	}
+
+	// Move the unread characters to the beginning of the buffer.
+	buffer_len := len(parser.buffer)
+	if parser.buffer_pos > 0 && parser.buffer_pos < buffer_len {
+		copy(parser.buffer, parser.buffer[parser.buffer_pos:])
+		buffer_len -= parser.buffer_pos
+		parser.buffer_pos = 0
+	} else if parser.buffer_pos == buffer_len {
+		buffer_len = 0
+		parser.buffer_pos = 0
+	}
+
+	// Open the whole buffer for writing, and cut it before returning.
+	parser.buffer = parser.buffer[:cap(parser.buffer)]
+
+	// Fill the buffer until it has enough characters.
+	first := true
+	for parser.unread < length {
+
+		// Fill the raw buffer if necessary.
+		if !first || parser.raw_buffer_pos == len(parser.raw_buffer) {
+			if !yaml_parser_update_raw_buffer(parser) {
+				parser.buffer = parser.buffer[:buffer_len]
+				return false
+			}
+		}
+		first = false
+
+		// Decode the raw buffer.
+	inner:
+		for parser.raw_buffer_pos != len(parser.raw_buffer) {
+			var value rune
+			var width int
+
+			raw_unread := len(parser.raw_buffer) - parser.raw_buffer_pos
+
+			// Decode the next character.
+			switch parser.encoding {
+			case yaml_UTF8_ENCODING:
+				// Decode a UTF-8 character.  Check RFC 3629
+				// (http://www.ietf.org/rfc/rfc3629.txt) for more details.
+				//
+				// The following table (taken from the RFC) is used for
+				// decoding.
+				//
+				//    Char. number range |        UTF-8 octet sequence
+				//      (hexadecimal)    |              (binary)
+				//   --------------------+------------------------------------
+				//   0000 0000-0000 007F | 0xxxxxxx
+				//   0000 0080-0000 07FF | 110xxxxx 10xxxxxx
+				//   0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
+				//   0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				//
+				// Additionally, the characters in the range 0xD800-0xDFFF
+				// are prohibited as they are reserved for use with UTF-16
+				// surrogate pairs.
+
+				// Determine the length of the UTF-8 sequence.
+				octet := parser.raw_buffer[parser.raw_buffer_pos]
+				switch {
+				case octet&0x80 == 0x00:
+					width = 1
+				case octet&0xE0 == 0xC0:
+					width = 2
+				case octet&0xF0 == 0xE0:
+					width = 3
+				case octet&0xF8 == 0xF0:
+					width = 4
+				default:
+					// The leading octet is invalid.
+					return yaml_parser_set_reader_error(parser,
+						"invalid leading UTF-8 octet",
+						parser.offset, int(octet))
+				}
+
+				// Check if the raw buffer contains an incomplete character.
+				if width > raw_unread {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-8 octet sequence",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Decode the leading octet.
+				switch {
+				case octet&0x80 == 0x00:
+					value = rune(octet & 0x7F)
+				case octet&0xE0 == 0xC0:
+					value = rune(octet & 0x1F)
+				case octet&0xF0 == 0xE0:
+					value = rune(octet & 0x0F)
+				case octet&0xF8 == 0xF0:
+					value = rune(octet & 0x07)
+				default:
+					value = 0
+				}
+
+				// Check and decode the trailing octets.
+				for k := 1; k < width; k++ {
+					octet = parser.raw_buffer[parser.raw_buffer_pos+k]
+
+					// Check if the octet is valid.
+					if (octet & 0xC0) != 0x80 {
+						return yaml_parser_set_reader_error(parser,
+							"invalid trailing UTF-8 octet",
+							parser.offset+k, int(octet))
+					}
+
+					// Decode the octet.
+					value = (value << 6) + rune(octet&0x3F)
+				}
+
+				// Check the length of the sequence against the value.
+				switch {
+				case width == 1:
+				case width == 2 && value >= 0x80:
+				case width == 3 && value >= 0x800:
+				case width == 4 && value >= 0x10000:
+				default:
+					return yaml_parser_set_reader_error(parser,
+						"invalid length of a UTF-8 sequence",
+						parser.offset, -1)
+				}
+
+				// Check the range of the value.
+				if value >= 0xD800 && value <= 0xDFFF || value > 0x10FFFF {
+					return yaml_parser_set_reader_error(parser,
+						"invalid Unicode character",
+						parser.offset, int(value))
+				}
+
+			case yaml_UTF16LE_ENCODING, yaml_UTF16BE_ENCODING:
+				var low, high int
+				if parser.encoding == yaml_UTF16LE_ENCODING {
+					low, high = 0, 1
+				} else {
+					low, high = 1, 0
+				}
+
+				// The UTF-16 encoding is not as simple as one might
+				// naively think.  Check RFC 2781
+				// (http://www.ietf.org/rfc/rfc2781.txt).
+				//
+				// Normally, two subsequent bytes describe a Unicode
+				// character.  However a special technique (called a
+				// surrogate pair) is used for specifying character
+				// values larger than 0xFFFF.
+				//
+				// A surrogate pair consists of two pseudo-characters:
+				//      high surrogate area (0xD800-0xDBFF)
+				//      low surrogate area (0xDC00-0xDFFF)
+				//
+				// The following formulas are used for decoding
+				// and encoding characters using surrogate pairs:
+				//
+				//  U  = U' + 0x10000   (0x01 00 00 <= U <= 0x10 FF FF)
+				//  U' = yyyyyyyyyyxxxxxxxxxx   (0 <= U' <= 0x0F FF FF)
+				//  W1 = 110110yyyyyyyyyy
+				//  W2 = 110111xxxxxxxxxx
+				//
+				// where U is the character value, W1 is the high surrogate
+				// area, W2 is the low surrogate area.
+
+				// Check for incomplete UTF-16 character.
+				if raw_unread < 2 {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-16 character",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Get the character.
+				value = rune(parser.raw_buffer[parser.raw_buffer_pos+low]) +
+					(rune(parser.raw_buffer[parser.raw_buffer_pos+high]) << 8)
+
+				// Check for unexpected low surrogate area.
+				if value&0xFC00 == 0xDC00 {
+					return yaml_parser_set_reader_error(parser,
+						"unexpected low surrogate area",
+						parser.offset, int(value))
+				}
+
+				// Check for a high surrogate area.
+				if value&0xFC00 == 0xD800 {
+					width = 4
+
+					// Check for incomplete surrogate pair.
+					if raw_unread < 4 {
+						if parser.eof {
+							return yaml_parser_set_reader_error(parser,
+								"incomplete UTF-16 surrogate pair",
+								parser.offset, -1)
+						}
+						break inner
+					}
+
+					// Get the next character.
+					value2 := rune(parser.raw_buffer[parser.raw_buffer_pos+low+2]) +
+						(rune(parser.raw_buffer[parser.raw_buffer_pos+high+2]) << 8)
+
+					// Check for a low surrogate area.
+					if value2&0xFC00 != 0xDC00 {
+						return yaml_parser_set_reader_error(parser,
+							"expected low surrogate area",
+							parser.offset+2, int(value2))
+					}
+
+					// Generate the value of the surrogate pair.
+					value = 0x10000 + ((value & 0x3FF) << 10) + (value2 & 0x3FF)
+				} else {
+					width = 2
+				}
+
+			default:
+				panic("impossible")
+			}
+
+			// Check if the character is in the allowed range:
+			//      #x9 | #xA | #xD | [#x20-#x7E]               (8 bit)
+			//      | #x85 | [#xA0-#xD7FF] | [#xE000-#xFFFD]    (16 bit)
+			//      | [#x10000-#x10FFFF]                        (32 bit)
+			switch {
+			case value == 0x09:
+			case value == 0x0A:
+			case value == 0x0D:
+			case value >= 0x20 && value <= 0x7E:
+			case value == 0x85:
+			case value >= 0xA0 && value <= 0xD7FF:
+			case value >= 0xE000 && value <= 0xFFFD:
+			case value >= 0x10000 && value <= 0x10FFFF:
+			default:
+				return yaml_parser_set_reader_error(parser,
+					"control characters are not allowed",
+					parser.offset, int(value))
+			}
+
+			// Move the raw pointers.
+			parser.raw_buffer_pos += width
+			parser.offset += width
+
+			// Finally put the character into the buffer.
+			if value <= 0x7F {
+				// 0000 0000-0000 007F . 0xxxxxxx
+				parser.buffer[buffer_len+0] = byte(value)
+				buffer_len += 1
+			} else if value <= 0x7FF {
+				// 0000 0080-0000 07FF . 110xxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xC0 + (value >> 6))
+				parser.buffer[buffer_len+1] = byte(0x80 + (value & 0x3F))
+				buffer_len += 2
+			} else if value <= 0xFFFF {
+				// 0000 0800-0000 FFFF . 1110xxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xE0 + (value >> 12))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + (value & 0x3F))
+				buffer_len += 3
+			} else {
+				// 0001 0000-0010 FFFF . 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xF0 + (value >> 18))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 12) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+3] = byte(0x80 + (value & 0x3F))
+				buffer_len += 4
+			}
+
+			parser.unread++
+		}
+
+		// On EOF, put NUL into the buffer and return.
+		if parser.eof {
+			parser.buffer[buffer_len] = 0
+			buffer_len++
+			parser.unread++
+			break
+		}
+	}
+	parser.buffer = parser.buffer[:buffer_len]
+	return true
+}
diff --git a/vendor/gopkg.in/yaml.v2/resolve.go b/vendor/gopkg.in/yaml.v2/resolve.go
new file mode 100644
index 000000000..93a863274
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/resolve.go
@@ -0,0 +1,203 @@
+package yaml
+
+import (
+	"encoding/base64"
+	"math"
+	"strconv"
+	"strings"
+	"unicode/utf8"
+)
+
+type resolveMapItem struct {
+	value interface{}
+	tag   string
+}
+
+var resolveTable = make([]byte, 256)
+var resolveMap = make(map[string]resolveMapItem)
+
+func init() {
+	t := resolveTable
+	t[int('+')] = 'S' // Sign
+	t[int('-')] = 'S'
+	for _, c := range "0123456789" {
+		t[int(c)] = 'D' // Digit
+	}
+	for _, c := range "yYnNtTfFoO~" {
+		t[int(c)] = 'M' // In map
+	}
+	t[int('.')] = '.' // Float (potentially in map)
+
+	var resolveMapList = []struct {
+		v   interface{}
+		tag string
+		l   []string
+	}{
+		{true, yaml_BOOL_TAG, []string{"y", "Y", "yes", "Yes", "YES"}},
+		{true, yaml_BOOL_TAG, []string{"true", "True", "TRUE"}},
+		{true, yaml_BOOL_TAG, []string{"on", "On", "ON"}},
+		{false, yaml_BOOL_TAG, []string{"n", "N", "no", "No", "NO"}},
+		{false, yaml_BOOL_TAG, []string{"false", "False", "FALSE"}},
+		{false, yaml_BOOL_TAG, []string{"off", "Off", "OFF"}},
+		{nil, yaml_NULL_TAG, []string{"", "~", "null", "Null", "NULL"}},
+		{math.NaN(), yaml_FLOAT_TAG, []string{".nan", ".NaN", ".NAN"}},
+		{math.Inf(+1), yaml_FLOAT_TAG, []string{".inf", ".Inf", ".INF"}},
+		{math.Inf(+1), yaml_FLOAT_TAG, []string{"+.inf", "+.Inf", "+.INF"}},
+		{math.Inf(-1), yaml_FLOAT_TAG, []string{"-.inf", "-.Inf", "-.INF"}},
+		{"<<", yaml_MERGE_TAG, []string{"<<"}},
+	}
+
+	m := resolveMap
+	for _, item := range resolveMapList {
+		for _, s := range item.l {
+			m[s] = resolveMapItem{item.v, item.tag}
+		}
+	}
+}
+
+const longTagPrefix = "tag:yaml.org,2002:"
+
+func shortTag(tag string) string {
+	// TODO This can easily be made faster and produce less garbage.
+	if strings.HasPrefix(tag, longTagPrefix) {
+		return "!!" + tag[len(longTagPrefix):]
+	}
+	return tag
+}
+
+func longTag(tag string) string {
+	if strings.HasPrefix(tag, "!!") {
+		return longTagPrefix + tag[2:]
+	}
+	return tag
+}
+
+func resolvableTag(tag string) bool {
+	switch tag {
+	case "", yaml_STR_TAG, yaml_BOOL_TAG, yaml_INT_TAG, yaml_FLOAT_TAG, yaml_NULL_TAG:
+		return true
+	}
+	return false
+}
+
+func resolve(tag string, in string) (rtag string, out interface{}) {
+	if !resolvableTag(tag) {
+		return tag, in
+	}
+
+	defer func() {
+		switch tag {
+		case "", rtag, yaml_STR_TAG, yaml_BINARY_TAG:
+			return
+		}
+		failf("cannot decode %s `%s` as a %s", shortTag(rtag), in, shortTag(tag))
+	}()
+
+	// Any data is accepted as a !!str or !!binary.
+	// Otherwise, the prefix is enough of a hint about what it might be.
+	hint := byte('N')
+	if in != "" {
+		hint = resolveTable[in[0]]
+	}
+	if hint != 0 && tag != yaml_STR_TAG && tag != yaml_BINARY_TAG {
+		// Handle things we can lookup in a map.
+		if item, ok := resolveMap[in]; ok {
+			return item.tag, item.value
+		}
+
+		// Base 60 floats are a bad idea, were dropped in YAML 1.2, and
+		// are purposefully unsupported here. They're still quoted on
+		// the way out for compatibility with other parser, though.
+
+		switch hint {
+		case 'M':
+			// We've already checked the map above.
+
+		case '.':
+			// Not in the map, so maybe a normal float.
+			floatv, err := strconv.ParseFloat(in, 64)
+			if err == nil {
+				return yaml_FLOAT_TAG, floatv
+			}
+
+		case 'D', 'S':
+			// Int, float, or timestamp.
+			plain := strings.Replace(in, "_", "", -1)
+			intv, err := strconv.ParseInt(plain, 0, 64)
+			if err == nil {
+				if intv == int64(int(intv)) {
+					return yaml_INT_TAG, int(intv)
+				} else {
+					return yaml_INT_TAG, intv
+				}
+			}
+			uintv, err := strconv.ParseUint(plain, 0, 64)
+			if err == nil {
+				return yaml_INT_TAG, uintv
+			}
+			floatv, err := strconv.ParseFloat(plain, 64)
+			if err == nil {
+				return yaml_FLOAT_TAG, floatv
+			}
+			if strings.HasPrefix(plain, "0b") {
+				intv, err := strconv.ParseInt(plain[2:], 2, 64)
+				if err == nil {
+					if intv == int64(int(intv)) {
+						return yaml_INT_TAG, int(intv)
+					} else {
+						return yaml_INT_TAG, intv
+					}
+				}
+				uintv, err := strconv.ParseUint(plain[2:], 2, 64)
+				if err == nil {
+					return yaml_INT_TAG, uintv
+				}
+			} else if strings.HasPrefix(plain, "-0b") {
+				intv, err := strconv.ParseInt(plain[3:], 2, 64)
+				if err == nil {
+					if intv == int64(int(intv)) {
+						return yaml_INT_TAG, -int(intv)
+					} else {
+						return yaml_INT_TAG, -intv
+					}
+				}
+			}
+			// XXX Handle timestamps here.
+
+		default:
+			panic("resolveTable item not yet handled: " + string(rune(hint)) + " (with " + in + ")")
+		}
+	}
+	if tag == yaml_BINARY_TAG {
+		return yaml_BINARY_TAG, in
+	}
+	if utf8.ValidString(in) {
+		return yaml_STR_TAG, in
+	}
+	return yaml_BINARY_TAG, encodeBase64(in)
+}
+
+// encodeBase64 encodes s as base64 that is broken up into multiple lines
+// as appropriate for the resulting length.
+func encodeBase64(s string) string {
+	const lineLen = 70
+	encLen := base64.StdEncoding.EncodedLen(len(s))
+	lines := encLen/lineLen + 1
+	buf := make([]byte, encLen*2+lines)
+	in := buf[0:encLen]
+	out := buf[encLen:]
+	base64.StdEncoding.Encode(in, []byte(s))
+	k := 0
+	for i := 0; i < len(in); i += lineLen {
+		j := i + lineLen
+		if j > len(in) {
+			j = len(in)
+		}
+		k += copy(out[k:], in[i:j])
+		if lines > 1 {
+			out[k] = '\n'
+			k++
+		}
+	}
+	return string(out[:k])
+}
diff --git a/vendor/gopkg.in/yaml.v2/scannerc.go b/vendor/gopkg.in/yaml.v2/scannerc.go
new file mode 100644
index 000000000..25808000f
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/scannerc.go
@@ -0,0 +1,2710 @@
+package yaml
+
+import (
+	"bytes"
+	"fmt"
+)
+
+// Introduction
+// ************
+//
+// The following notes assume that you are familiar with the YAML specification
+// (http://yaml.org/spec/cvs/current.html).  We mostly follow it, although in
+// some cases we are less restrictive that it requires.
+//
+// The process of transforming a YAML stream into a sequence of events is
+// divided on two steps: Scanning and Parsing.
+//
+// The Scanner transforms the input stream into a sequence of tokens, while the
+// parser transform the sequence of tokens produced by the Scanner into a
+// sequence of parsing events.
+//
+// The Scanner is rather clever and complicated. The Parser, on the contrary,
+// is a straightforward implementation of a recursive-descendant parser (or,
+// LL(1) parser, as it is usually called).
+//
+// Actually there are two issues of Scanning that might be called "clever", the
+// rest is quite straightforward.  The issues are "block collection start" and
+// "simple keys".  Both issues are explained below in details.
+//
+// Here the Scanning step is explained and implemented.  We start with the list
+// of all the tokens produced by the Scanner together with short descriptions.
+//
+// Now, tokens:
+//
+//      STREAM-START(encoding)          # The stream start.
+//      STREAM-END                      # The stream end.
+//      VERSION-DIRECTIVE(major,minor)  # The '%YAML' directive.
+//      TAG-DIRECTIVE(handle,prefix)    # The '%TAG' directive.
+//      DOCUMENT-START                  # '---'
+//      DOCUMENT-END                    # '...'
+//      BLOCK-SEQUENCE-START            # Indentation increase denoting a block
+//      BLOCK-MAPPING-START             # sequence or a block mapping.
+//      BLOCK-END                       # Indentation decrease.
+//      FLOW-SEQUENCE-START             # '['
+//      FLOW-SEQUENCE-END               # ']'
+//      BLOCK-SEQUENCE-START            # '{'
+//      BLOCK-SEQUENCE-END              # '}'
+//      BLOCK-ENTRY                     # '-'
+//      FLOW-ENTRY                      # ','
+//      KEY                             # '?' or nothing (simple keys).
+//      VALUE                           # ':'
+//      ALIAS(anchor)                   # '*anchor'
+//      ANCHOR(anchor)                  # '&anchor'
+//      TAG(handle,suffix)              # '!handle!suffix'
+//      SCALAR(value,style)             # A scalar.
+//
+// The following two tokens are "virtual" tokens denoting the beginning and the
+// end of the stream:
+//
+//      STREAM-START(encoding)
+//      STREAM-END
+//
+// We pass the information about the input stream encoding with the
+// STREAM-START token.
+//
+// The next two tokens are responsible for tags:
+//
+//      VERSION-DIRECTIVE(major,minor)
+//      TAG-DIRECTIVE(handle,prefix)
+//
+// Example:
+//
+//      %YAML   1.1
+//      %TAG    !   !foo
+//      %TAG    !yaml!  tag:yaml.org,2002:
+//      ---
+//
+// The correspoding sequence of tokens:
+//
+//      STREAM-START(utf-8)
+//      VERSION-DIRECTIVE(1,1)
+//      TAG-DIRECTIVE("!","!foo")
+//      TAG-DIRECTIVE("!yaml","tag:yaml.org,2002:")
+//      DOCUMENT-START
+//      STREAM-END
+//
+// Note that the VERSION-DIRECTIVE and TAG-DIRECTIVE tokens occupy a whole
+// line.
+//
+// The document start and end indicators are represented by:
+//
+//      DOCUMENT-START
+//      DOCUMENT-END
+//
+// Note that if a YAML stream contains an implicit document (without '---'
+// and '...' indicators), no DOCUMENT-START and DOCUMENT-END tokens will be
+// produced.
+//
+// In the following examples, we present whole documents together with the
+// produced tokens.
+//
+//      1. An implicit document:
+//
+//          'a scalar'
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          SCALAR("a scalar",single-quoted)
+//          STREAM-END
+//
+//      2. An explicit document:
+//
+//          ---
+//          'a scalar'
+//          ...
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          DOCUMENT-START
+//          SCALAR("a scalar",single-quoted)
+//          DOCUMENT-END
+//          STREAM-END
+//
+//      3. Several documents in a stream:
+//
+//          'a scalar'
+//          ---
+//          'another scalar'
+//          ---
+//          'yet another scalar'
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          SCALAR("a scalar",single-quoted)
+//          DOCUMENT-START
+//          SCALAR("another scalar",single-quoted)
+//          DOCUMENT-START
+//          SCALAR("yet another scalar",single-quoted)
+//          STREAM-END
+//
+// We have already introduced the SCALAR token above.  The following tokens are
+// used to describe aliases, anchors, tag, and scalars:
+//
+//      ALIAS(anchor)
+//      ANCHOR(anchor)
+//      TAG(handle,suffix)
+//      SCALAR(value,style)
+//
+// The following series of examples illustrate the usage of these tokens:
+//
+//      1. A recursive sequence:
+//
+//          &A [ *A ]
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          ANCHOR("A")
+//          FLOW-SEQUENCE-START
+//          ALIAS("A")
+//          FLOW-SEQUENCE-END
+//          STREAM-END
+//
+//      2. A tagged scalar:
+//
+//          !!float "3.14"  # A good approximation.
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          TAG("!!","float")
+//          SCALAR("3.14",double-quoted)
+//          STREAM-END
+//
+//      3. Various scalar styles:
+//
+//          --- # Implicit empty plain scalars do not produce tokens.
+//          --- a plain scalar
+//          --- 'a single-quoted scalar'
+//          --- "a double-quoted scalar"
+//          --- |-
+//            a literal scalar
+//          --- >-
+//            a folded
+//            scalar
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          DOCUMENT-START
+//          DOCUMENT-START
+//          SCALAR("a plain scalar",plain)
+//          DOCUMENT-START
+//          SCALAR("a single-quoted scalar",single-quoted)
+//          DOCUMENT-START
+//          SCALAR("a double-quoted scalar",double-quoted)
+//          DOCUMENT-START
+//          SCALAR("a literal scalar",literal)
+//          DOCUMENT-START
+//          SCALAR("a folded scalar",folded)
+//          STREAM-END
+//
+// Now it's time to review collection-related tokens. We will start with
+// flow collections:
+//
+//      FLOW-SEQUENCE-START
+//      FLOW-SEQUENCE-END
+//      FLOW-MAPPING-START
+//      FLOW-MAPPING-END
+//      FLOW-ENTRY
+//      KEY
+//      VALUE
+//
+// The tokens FLOW-SEQUENCE-START, FLOW-SEQUENCE-END, FLOW-MAPPING-START, and
+// FLOW-MAPPING-END represent the indicators '[', ']', '{', and '}'
+// correspondingly.  FLOW-ENTRY represent the ',' indicator.  Finally the
+// indicators '?' and ':', which are used for denoting mapping keys and values,
+// are represented by the KEY and VALUE tokens.
+//
+// The following examples show flow collections:
+//
+//      1. A flow sequence:
+//
+//          [item 1, item 2, item 3]
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          FLOW-SEQUENCE-START
+//          SCALAR("item 1",plain)
+//          FLOW-ENTRY
+//          SCALAR("item 2",plain)
+//          FLOW-ENTRY
+//          SCALAR("item 3",plain)
+//          FLOW-SEQUENCE-END
+//          STREAM-END
+//
+//      2. A flow mapping:
+//
+//          {
+//              a simple key: a value,  # Note that the KEY token is produced.
+//              ? a complex key: another value,
+//          }
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          FLOW-MAPPING-START
+//          KEY
+//          SCALAR("a simple key",plain)
+//          VALUE
+//          SCALAR("a value",plain)
+//          FLOW-ENTRY
+//          KEY
+//          SCALAR("a complex key",plain)
+//          VALUE
+//          SCALAR("another value",plain)
+//          FLOW-ENTRY
+//          FLOW-MAPPING-END
+//          STREAM-END
+//
+// A simple key is a key which is not denoted by the '?' indicator.  Note that
+// the Scanner still produce the KEY token whenever it encounters a simple key.
+//
+// For scanning block collections, the following tokens are used (note that we
+// repeat KEY and VALUE here):
+//
+//      BLOCK-SEQUENCE-START
+//      BLOCK-MAPPING-START
+//      BLOCK-END
+//      BLOCK-ENTRY
+//      KEY
+//      VALUE
+//
+// The tokens BLOCK-SEQUENCE-START and BLOCK-MAPPING-START denote indentation
+// increase that precedes a block collection (cf. the INDENT token in Python).
+// The token BLOCK-END denote indentation decrease that ends a block collection
+// (cf. the DEDENT token in Python).  However YAML has some syntax pecularities
+// that makes detections of these tokens more complex.
+//
+// The tokens BLOCK-ENTRY, KEY, and VALUE are used to represent the indicators
+// '-', '?', and ':' correspondingly.
+//
+// The following examples show how the tokens BLOCK-SEQUENCE-START,
+// BLOCK-MAPPING-START, and BLOCK-END are emitted by the Scanner:
+//
+//      1. Block sequences:
+//
+//          - item 1
+//          - item 2
+//          -
+//            - item 3.1
+//            - item 3.2
+//          -
+//            key 1: value 1
+//            key 2: value 2
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          BLOCK-SEQUENCE-START
+//          BLOCK-ENTRY
+//          SCALAR("item 1",plain)
+//          BLOCK-ENTRY
+//          SCALAR("item 2",plain)
+//          BLOCK-ENTRY
+//          BLOCK-SEQUENCE-START
+//          BLOCK-ENTRY
+//          SCALAR("item 3.1",plain)
+//          BLOCK-ENTRY
+//          SCALAR("item 3.2",plain)
+//          BLOCK-END
+//          BLOCK-ENTRY
+//          BLOCK-MAPPING-START
+//          KEY
+//          SCALAR("key 1",plain)
+//          VALUE
+//          SCALAR("value 1",plain)
+//          KEY
+//          SCALAR("key 2",plain)
+//          VALUE
+//          SCALAR("value 2",plain)
+//          BLOCK-END
+//          BLOCK-END
+//          STREAM-END
+//
+//      2. Block mappings:
+//
+//          a simple key: a value   # The KEY token is produced here.
+//          ? a complex key
+//          : another value
+//          a mapping:
+//            key 1: value 1
+//            key 2: value 2
+//          a sequence:
+//            - item 1
+//            - item 2
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          BLOCK-MAPPING-START
+//          KEY
+//          SCALAR("a simple key",plain)
+//          VALUE
+//          SCALAR("a value",plain)
+//          KEY
+//          SCALAR("a complex key",plain)
+//          VALUE
+//          SCALAR("another value",plain)
+//          KEY
+//          SCALAR("a mapping",plain)
+//          BLOCK-MAPPING-START
+//          KEY
+//          SCALAR("key 1",plain)
+//          VALUE
+//          SCALAR("value 1",plain)
+//          KEY
+//          SCALAR("key 2",plain)
+//          VALUE
+//          SCALAR("value 2",plain)
+//          BLOCK-END
+//          KEY
+//          SCALAR("a sequence",plain)
+//          VALUE
+//          BLOCK-SEQUENCE-START
+//          BLOCK-ENTRY
+//          SCALAR("item 1",plain)
+//          BLOCK-ENTRY
+//          SCALAR("item 2",plain)
+//          BLOCK-END
+//          BLOCK-END
+//          STREAM-END
+//
+// YAML does not always require to start a new block collection from a new
+// line.  If the current line contains only '-', '?', and ':' indicators, a new
+// block collection may start at the current line.  The following examples
+// illustrate this case:
+//
+//      1. Collections in a sequence:
+//
+//          - - item 1
+//            - item 2
+//          - key 1: value 1
+//            key 2: value 2
+//          - ? complex key
+//            : complex value
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          BLOCK-SEQUENCE-START
+//          BLOCK-ENTRY
+//          BLOCK-SEQUENCE-START
+//          BLOCK-ENTRY
+//          SCALAR("item 1",plain)
+//          BLOCK-ENTRY
+//          SCALAR("item 2",plain)
+//          BLOCK-END
+//          BLOCK-ENTRY
+//          BLOCK-MAPPING-START
+//          KEY
+//          SCALAR("key 1",plain)
+//          VALUE
+//          SCALAR("value 1",plain)
+//          KEY
+//          SCALAR("key 2",plain)
+//          VALUE
+//          SCALAR("value 2",plain)
+//          BLOCK-END
+//          BLOCK-ENTRY
+//          BLOCK-MAPPING-START
+//          KEY
+//          SCALAR("complex key")
+//          VALUE
+//          SCALAR("complex value")
+//          BLOCK-END
+//          BLOCK-END
+//          STREAM-END
+//
+//      2. Collections in a mapping:
+//
+//          ? a sequence
+//          : - item 1
+//            - item 2
+//          ? a mapping
+//          : key 1: value 1
+//            key 2: value 2
+//
+//      Tokens:
+//
+//          STREAM-START(utf-8)
+//          BLOCK-MAPPING-START
+//          KEY
+//          SCALAR("a sequence",plain)
+//          VALUE
+//          BLOCK-SEQUENCE-START
+//          BLOCK-ENTRY
+//          SCALAR("item 1",plain)
+//          BLOCK-ENTRY
+//          SCALAR("item 2",plain)
+//          BLOCK-END
+//          KEY
+//          SCALAR("a mapping",plain)
+//          VALUE
+//          BLOCK-MAPPING-START
+//          KEY
+//          SCALAR("key 1",plain)
+//          VALUE
+//          SCALAR("value 1",plain)
+//          KEY
+//          SCALAR("key 2",plain)
+//          VALUE
+//          SCALAR("value 2",plain)
+//          BLOCK-END
+//          BLOCK-END
+//          STREAM-END
+//
+// YAML also permits non-indented sequences if they are included into a block
+// mapping.  In this case, the token BLOCK-SEQUENCE-START is not produced:
+//
+//      key:
+//      - item 1    # BLOCK-SEQUENCE-START is NOT produced here.
+//      - item 2
+//
+// Tokens:
+//
+//      STREAM-START(utf-8)
+//      BLOCK-MAPPING-START
+//      KEY
+//      SCALAR("key",plain)
+//      VALUE
+//      BLOCK-ENTRY
+//      SCALAR("item 1",plain)
+//      BLOCK-ENTRY
+//      SCALAR("item 2",plain)
+//      BLOCK-END
+//
+
+// Ensure that the buffer contains the required number of characters.
+// Return true on success, false on failure (reader error or memory error).
+func cache(parser *yaml_parser_t, length int) bool {
+	// [Go] This was inlined: !cache(A, B) -> unread < B && !update(A, B)
+	return parser.unread >= length || yaml_parser_update_buffer(parser, length)
+}
+
+// Advance the buffer pointer.
+func skip(parser *yaml_parser_t) {
+	parser.mark.index++
+	parser.mark.column++
+	parser.unread--
+	parser.buffer_pos += width(parser.buffer[parser.buffer_pos])
+}
+
+func skip_line(parser *yaml_parser_t) {
+	if is_crlf(parser.buffer, parser.buffer_pos) {
+		parser.mark.index += 2
+		parser.mark.column = 0
+		parser.mark.line++
+		parser.unread -= 2
+		parser.buffer_pos += 2
+	} else if is_break(parser.buffer, parser.buffer_pos) {
+		parser.mark.index++
+		parser.mark.column = 0
+		parser.mark.line++
+		parser.unread--
+		parser.buffer_pos += width(parser.buffer[parser.buffer_pos])
+	}
+}
+
+// Copy a character to a string buffer and advance pointers.
+func read(parser *yaml_parser_t, s []byte) []byte {
+	w := width(parser.buffer[parser.buffer_pos])
+	if w == 0 {
+		panic("invalid character sequence")
+	}
+	if len(s) == 0 {
+		s = make([]byte, 0, 32)
+	}
+	if w == 1 && len(s)+w <= cap(s) {
+		s = s[:len(s)+1]
+		s[len(s)-1] = parser.buffer[parser.buffer_pos]
+		parser.buffer_pos++
+	} else {
+		s = append(s, parser.buffer[parser.buffer_pos:parser.buffer_pos+w]...)
+		parser.buffer_pos += w
+	}
+	parser.mark.index++
+	parser.mark.column++
+	parser.unread--
+	return s
+}
+
+// Copy a line break character to a string buffer and advance pointers.
+func read_line(parser *yaml_parser_t, s []byte) []byte {
+	buf := parser.buffer
+	pos := parser.buffer_pos
+	switch {
+	case buf[pos] == '\r' && buf[pos+1] == '\n':
+		// CR LF . LF
+		s = append(s, '\n')
+		parser.buffer_pos += 2
+		parser.mark.index++
+		parser.unread--
+	case buf[pos] == '\r' || buf[pos] == '\n':
+		// CR|LF . LF
+		s = append(s, '\n')
+		parser.buffer_pos += 1
+	case buf[pos] == '\xC2' && buf[pos+1] == '\x85':
+		// NEL . LF
+		s = append(s, '\n')
+		parser.buffer_pos += 2
+	case buf[pos] == '\xE2' && buf[pos+1] == '\x80' && (buf[pos+2] == '\xA8' || buf[pos+2] == '\xA9'):
+		// LS|PS . LS|PS
+		s = append(s, buf[parser.buffer_pos:pos+3]...)
+		parser.buffer_pos += 3
+	default:
+		return s
+	}
+	parser.mark.index++
+	parser.mark.column = 0
+	parser.mark.line++
+	parser.unread--
+	return s
+}
+
+// Get the next token.
+func yaml_parser_scan(parser *yaml_parser_t, token *yaml_token_t) bool {
+	// Erase the token object.
+	*token = yaml_token_t{} // [Go] Is this necessary?
+
+	// No tokens after STREAM-END or error.
+	if parser.stream_end_produced || parser.error != yaml_NO_ERROR {
+		return true
+	}
+
+	// Ensure that the tokens queue contains enough tokens.
+	if !parser.token_available {
+		if !yaml_parser_fetch_more_tokens(parser) {
+			return false
+		}
+	}
+
+	// Fetch the next token from the queue.
+	*token = parser.tokens[parser.tokens_head]
+	parser.tokens_head++
+	parser.tokens_parsed++
+	parser.token_available = false
+
+	if token.typ == yaml_STREAM_END_TOKEN {
+		parser.stream_end_produced = true
+	}
+	return true
+}
+
+// Set the scanner error and return false.
+func yaml_parser_set_scanner_error(parser *yaml_parser_t, context string, context_mark yaml_mark_t, problem string) bool {
+	parser.error = yaml_SCANNER_ERROR
+	parser.context = context
+	parser.context_mark = context_mark
+	parser.problem = problem
+	parser.problem_mark = parser.mark
+	return false
+}
+
+func yaml_parser_set_scanner_tag_error(parser *yaml_parser_t, directive bool, context_mark yaml_mark_t, problem string) bool {
+	context := "while parsing a tag"
+	if directive {
+		context = "while parsing a %TAG directive"
+	}
+	return yaml_parser_set_scanner_error(parser, context, context_mark, "did not find URI escaped octet")
+}
+
+func trace(args ...interface{}) func() {
+	pargs := append([]interface{}{"+++"}, args...)
+	fmt.Println(pargs...)
+	pargs = append([]interface{}{"---"}, args...)
+	return func() { fmt.Println(pargs...) }
+}
+
+// Ensure that the tokens queue contains at least one token which can be
+// returned to the Parser.
+func yaml_parser_fetch_more_tokens(parser *yaml_parser_t) bool {
+	// While we need more tokens to fetch, do it.
+	for {
+		// Check if we really need to fetch more tokens.
+		need_more_tokens := false
+
+		if parser.tokens_head == len(parser.tokens) {
+			// Queue is empty.
+			need_more_tokens = true
+		} else {
+			// Check if any potential simple key may occupy the head position.
+			if !yaml_parser_stale_simple_keys(parser) {
+				return false
+			}
+
+			for i := range parser.simple_keys {
+				simple_key := &parser.simple_keys[i]
+				if simple_key.possible && simple_key.token_number == parser.tokens_parsed {
+					need_more_tokens = true
+					break
+				}
+			}
+		}
+
+		// We are finished.
+		if !need_more_tokens {
+			break
+		}
+		// Fetch the next token.
+		if !yaml_parser_fetch_next_token(parser) {
+			return false
+		}
+	}
+
+	parser.token_available = true
+	return true
+}
+
+// The dispatcher for token fetchers.
+func yaml_parser_fetch_next_token(parser *yaml_parser_t) bool {
+	// Ensure that the buffer is initialized.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+
+	// Check if we just started scanning.  Fetch STREAM-START then.
+	if !parser.stream_start_produced {
+		return yaml_parser_fetch_stream_start(parser)
+	}
+
+	// Eat whitespaces and comments until we reach the next token.
+	if !yaml_parser_scan_to_next_token(parser) {
+		return false
+	}
+
+	// Remove obsolete potential simple keys.
+	if !yaml_parser_stale_simple_keys(parser) {
+		return false
+	}
+
+	// Check the indentation level against the current column.
+	if !yaml_parser_unroll_indent(parser, parser.mark.column) {
+		return false
+	}
+
+	// Ensure that the buffer contains at least 4 characters.  4 is the length
+	// of the longest indicators ('--- ' and '... ').
+	if parser.unread < 4 && !yaml_parser_update_buffer(parser, 4) {
+		return false
+	}
+
+	// Is it the end of the stream?
+	if is_z(parser.buffer, parser.buffer_pos) {
+		return yaml_parser_fetch_stream_end(parser)
+	}
+
+	// Is it a directive?
+	if parser.mark.column == 0 && parser.buffer[parser.buffer_pos] == '%' {
+		return yaml_parser_fetch_directive(parser)
+	}
+
+	buf := parser.buffer
+	pos := parser.buffer_pos
+
+	// Is it the document start indicator?
+	if parser.mark.column == 0 && buf[pos] == '-' && buf[pos+1] == '-' && buf[pos+2] == '-' && is_blankz(buf, pos+3) {
+		return yaml_parser_fetch_document_indicator(parser, yaml_DOCUMENT_START_TOKEN)
+	}
+
+	// Is it the document end indicator?
+	if parser.mark.column == 0 && buf[pos] == '.' && buf[pos+1] == '.' && buf[pos+2] == '.' && is_blankz(buf, pos+3) {
+		return yaml_parser_fetch_document_indicator(parser, yaml_DOCUMENT_END_TOKEN)
+	}
+
+	// Is it the flow sequence start indicator?
+	if buf[pos] == '[' {
+		return yaml_parser_fetch_flow_collection_start(parser, yaml_FLOW_SEQUENCE_START_TOKEN)
+	}
+
+	// Is it the flow mapping start indicator?
+	if parser.buffer[parser.buffer_pos] == '{' {
+		return yaml_parser_fetch_flow_collection_start(parser, yaml_FLOW_MAPPING_START_TOKEN)
+	}
+
+	// Is it the flow sequence end indicator?
+	if parser.buffer[parser.buffer_pos] == ']' {
+		return yaml_parser_fetch_flow_collection_end(parser,
+			yaml_FLOW_SEQUENCE_END_TOKEN)
+	}
+
+	// Is it the flow mapping end indicator?
+	if parser.buffer[parser.buffer_pos] == '}' {
+		return yaml_parser_fetch_flow_collection_end(parser,
+			yaml_FLOW_MAPPING_END_TOKEN)
+	}
+
+	// Is it the flow entry indicator?
+	if parser.buffer[parser.buffer_pos] == ',' {
+		return yaml_parser_fetch_flow_entry(parser)
+	}
+
+	// Is it the block entry indicator?
+	if parser.buffer[parser.buffer_pos] == '-' && is_blankz(parser.buffer, parser.buffer_pos+1) {
+		return yaml_parser_fetch_block_entry(parser)
+	}
+
+	// Is it the key indicator?
+	if parser.buffer[parser.buffer_pos] == '?' && (parser.flow_level > 0 || is_blankz(parser.buffer, parser.buffer_pos+1)) {
+		return yaml_parser_fetch_key(parser)
+	}
+
+	// Is it the value indicator?
+	if parser.buffer[parser.buffer_pos] == ':' && (parser.flow_level > 0 || is_blankz(parser.buffer, parser.buffer_pos+1)) {
+		return yaml_parser_fetch_value(parser)
+	}
+
+	// Is it an alias?
+	if parser.buffer[parser.buffer_pos] == '*' {
+		return yaml_parser_fetch_anchor(parser, yaml_ALIAS_TOKEN)
+	}
+
+	// Is it an anchor?
+	if parser.buffer[parser.buffer_pos] == '&' {
+		return yaml_parser_fetch_anchor(parser, yaml_ANCHOR_TOKEN)
+	}
+
+	// Is it a tag?
+	if parser.buffer[parser.buffer_pos] == '!' {
+		return yaml_parser_fetch_tag(parser)
+	}
+
+	// Is it a literal scalar?
+	if parser.buffer[parser.buffer_pos] == '|' && parser.flow_level == 0 {
+		return yaml_parser_fetch_block_scalar(parser, true)
+	}
+
+	// Is it a folded scalar?
+	if parser.buffer[parser.buffer_pos] == '>' && parser.flow_level == 0 {
+		return yaml_parser_fetch_block_scalar(parser, false)
+	}
+
+	// Is it a single-quoted scalar?
+	if parser.buffer[parser.buffer_pos] == '\'' {
+		return yaml_parser_fetch_flow_scalar(parser, true)
+	}
+
+	// Is it a double-quoted scalar?
+	if parser.buffer[parser.buffer_pos] == '"' {
+		return yaml_parser_fetch_flow_scalar(parser, false)
+	}
+
+	// Is it a plain scalar?
+	//
+	// A plain scalar may start with any non-blank characters except
+	//
+	//      '-', '?', ':', ',', '[', ']', '{', '}',
+	//      '#', '&', '*', '!', '|', '>', '\'', '\"',
+	//      '%', '@', '`'.
+	//
+	// In the block context (and, for the '-' indicator, in the flow context
+	// too), it may also start with the characters
+	//
+	//      '-', '?', ':'
+	//
+	// if it is followed by a non-space character.
+	//
+	// The last rule is more restrictive than the specification requires.
+	// [Go] Make this logic more reasonable.
+	//switch parser.buffer[parser.buffer_pos] {
+	//case '-', '?', ':', ',', '?', '-', ',', ':', ']', '[', '}', '{', '&', '#', '!', '*', '>', '|', '"', '\'', '@', '%', '-', '`':
+	//}
+	if !(is_blankz(parser.buffer, parser.buffer_pos) || parser.buffer[parser.buffer_pos] == '-' ||
+		parser.buffer[parser.buffer_pos] == '?' || parser.buffer[parser.buffer_pos] == ':' ||
+		parser.buffer[parser.buffer_pos] == ',' || parser.buffer[parser.buffer_pos] == '[' ||
+		parser.buffer[parser.buffer_pos] == ']' || parser.buffer[parser.buffer_pos] == '{' ||
+		parser.buffer[parser.buffer_pos] == '}' || parser.buffer[parser.buffer_pos] == '#' ||
+		parser.buffer[parser.buffer_pos] == '&' || parser.buffer[parser.buffer_pos] == '*' ||
+		parser.buffer[parser.buffer_pos] == '!' || parser.buffer[parser.buffer_pos] == '|' ||
+		parser.buffer[parser.buffer_pos] == '>' || parser.buffer[parser.buffer_pos] == '\'' ||
+		parser.buffer[parser.buffer_pos] == '"' || parser.buffer[parser.buffer_pos] == '%' ||
+		parser.buffer[parser.buffer_pos] == '@' || parser.buffer[parser.buffer_pos] == '`') ||
+		(parser.buffer[parser.buffer_pos] == '-' && !is_blank(parser.buffer, parser.buffer_pos+1)) ||
+		(parser.flow_level == 0 &&
+			(parser.buffer[parser.buffer_pos] == '?' || parser.buffer[parser.buffer_pos] == ':') &&
+			!is_blankz(parser.buffer, parser.buffer_pos+1)) {
+		return yaml_parser_fetch_plain_scalar(parser)
+	}
+
+	// If we don't determine the token type so far, it is an error.
+	return yaml_parser_set_scanner_error(parser,
+		"while scanning for the next token", parser.mark,
+		"found character that cannot start any token")
+}
+
+// Check the list of potential simple keys and remove the positions that
+// cannot contain simple keys anymore.
+func yaml_parser_stale_simple_keys(parser *yaml_parser_t) bool {
+	// Check for a potential simple key for each flow level.
+	for i := range parser.simple_keys {
+		simple_key := &parser.simple_keys[i]
+
+		// The specification requires that a simple key
+		//
+		//  - is limited to a single line,
+		//  - is shorter than 1024 characters.
+		if simple_key.possible && (simple_key.mark.line < parser.mark.line || simple_key.mark.index+1024 < parser.mark.index) {
+
+			// Check if the potential simple key to be removed is required.
+			if simple_key.required {
+				return yaml_parser_set_scanner_error(parser,
+					"while scanning a simple key", simple_key.mark,
+					"could not find expected ':'")
+			}
+			simple_key.possible = false
+		}
+	}
+	return true
+}
+
+// Check if a simple key may start at the current position and add it if
+// needed.
+func yaml_parser_save_simple_key(parser *yaml_parser_t) bool {
+	// A simple key is required at the current position if the scanner is in
+	// the block context and the current column coincides with the indentation
+	// level.
+
+	required := parser.flow_level == 0 && parser.indent == parser.mark.column
+
+	// A simple key is required only when it is the first token in the current
+	// line.  Therefore it is always allowed.  But we add a check anyway.
+	if required && !parser.simple_key_allowed {
+		panic("should not happen")
+	}
+
+	//
+	// If the current position may start a simple key, save it.
+	//
+	if parser.simple_key_allowed {
+		simple_key := yaml_simple_key_t{
+			possible:     true,
+			required:     required,
+			token_number: parser.tokens_parsed + (len(parser.tokens) - parser.tokens_head),
+		}
+		simple_key.mark = parser.mark
+
+		if !yaml_parser_remove_simple_key(parser) {
+			return false
+		}
+		parser.simple_keys[len(parser.simple_keys)-1] = simple_key
+	}
+	return true
+}
+
+// Remove a potential simple key at the current flow level.
+func yaml_parser_remove_simple_key(parser *yaml_parser_t) bool {
+	i := len(parser.simple_keys) - 1
+	if parser.simple_keys[i].possible {
+		// If the key is required, it is an error.
+		if parser.simple_keys[i].required {
+			return yaml_parser_set_scanner_error(parser,
+				"while scanning a simple key", parser.simple_keys[i].mark,
+				"could not find expected ':'")
+		}
+	}
+	// Remove the key from the stack.
+	parser.simple_keys[i].possible = false
+	return true
+}
+
+// Increase the flow level and resize the simple key list if needed.
+func yaml_parser_increase_flow_level(parser *yaml_parser_t) bool {
+	// Reset the simple key on the next level.
+	parser.simple_keys = append(parser.simple_keys, yaml_simple_key_t{})
+
+	// Increase the flow level.
+	parser.flow_level++
+	return true
+}
+
+// Decrease the flow level.
+func yaml_parser_decrease_flow_level(parser *yaml_parser_t) bool {
+	if parser.flow_level > 0 {
+		parser.flow_level--
+		parser.simple_keys = parser.simple_keys[:len(parser.simple_keys)-1]
+	}
+	return true
+}
+
+// Push the current indentation level to the stack and set the new level
+// the current column is greater than the indentation level.  In this case,
+// append or insert the specified token into the token queue.
+func yaml_parser_roll_indent(parser *yaml_parser_t, column, number int, typ yaml_token_type_t, mark yaml_mark_t) bool {
+	// In the flow context, do nothing.
+	if parser.flow_level > 0 {
+		return true
+	}
+
+	if parser.indent < column {
+		// Push the current indentation level to the stack and set the new
+		// indentation level.
+		parser.indents = append(parser.indents, parser.indent)
+		parser.indent = column
+
+		// Create a token and insert it into the queue.
+		token := yaml_token_t{
+			typ:        typ,
+			start_mark: mark,
+			end_mark:   mark,
+		}
+		if number > -1 {
+			number -= parser.tokens_parsed
+		}
+		yaml_insert_token(parser, number, &token)
+	}
+	return true
+}
+
+// Pop indentation levels from the indents stack until the current level
+// becomes less or equal to the column.  For each indentation level, append
+// the BLOCK-END token.
+func yaml_parser_unroll_indent(parser *yaml_parser_t, column int) bool {
+	// In the flow context, do nothing.
+	if parser.flow_level > 0 {
+		return true
+	}
+
+	// Loop through the indentation levels in the stack.
+	for parser.indent > column {
+		// Create a token and append it to the queue.
+		token := yaml_token_t{
+			typ:        yaml_BLOCK_END_TOKEN,
+			start_mark: parser.mark,
+			end_mark:   parser.mark,
+		}
+		yaml_insert_token(parser, -1, &token)
+
+		// Pop the indentation level.
+		parser.indent = parser.indents[len(parser.indents)-1]
+		parser.indents = parser.indents[:len(parser.indents)-1]
+	}
+	return true
+}
+
+// Initialize the scanner and produce the STREAM-START token.
+func yaml_parser_fetch_stream_start(parser *yaml_parser_t) bool {
+
+	// Set the initial indentation.
+	parser.indent = -1
+
+	// Initialize the simple key stack.
+	parser.simple_keys = append(parser.simple_keys, yaml_simple_key_t{})
+
+	// A simple key is allowed at the beginning of the stream.
+	parser.simple_key_allowed = true
+
+	// We have started.
+	parser.stream_start_produced = true
+
+	// Create the STREAM-START token and append it to the queue.
+	token := yaml_token_t{
+		typ:        yaml_STREAM_START_TOKEN,
+		start_mark: parser.mark,
+		end_mark:   parser.mark,
+		encoding:   parser.encoding,
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the STREAM-END token and shut down the scanner.
+func yaml_parser_fetch_stream_end(parser *yaml_parser_t) bool {
+
+	// Force new line.
+	if parser.mark.column != 0 {
+		parser.mark.column = 0
+		parser.mark.line++
+	}
+
+	// Reset the indentation level.
+	if !yaml_parser_unroll_indent(parser, -1) {
+		return false
+	}
+
+	// Reset simple keys.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	parser.simple_key_allowed = false
+
+	// Create the STREAM-END token and append it to the queue.
+	token := yaml_token_t{
+		typ:        yaml_STREAM_END_TOKEN,
+		start_mark: parser.mark,
+		end_mark:   parser.mark,
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce a VERSION-DIRECTIVE or TAG-DIRECTIVE token.
+func yaml_parser_fetch_directive(parser *yaml_parser_t) bool {
+	// Reset the indentation level.
+	if !yaml_parser_unroll_indent(parser, -1) {
+		return false
+	}
+
+	// Reset simple keys.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	parser.simple_key_allowed = false
+
+	// Create the YAML-DIRECTIVE or TAG-DIRECTIVE token.
+	token := yaml_token_t{}
+	if !yaml_parser_scan_directive(parser, &token) {
+		return false
+	}
+	// Append the token to the queue.
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the DOCUMENT-START or DOCUMENT-END token.
+func yaml_parser_fetch_document_indicator(parser *yaml_parser_t, typ yaml_token_type_t) bool {
+	// Reset the indentation level.
+	if !yaml_parser_unroll_indent(parser, -1) {
+		return false
+	}
+
+	// Reset simple keys.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	parser.simple_key_allowed = false
+
+	// Consume the token.
+	start_mark := parser.mark
+
+	skip(parser)
+	skip(parser)
+	skip(parser)
+
+	end_mark := parser.mark
+
+	// Create the DOCUMENT-START or DOCUMENT-END token.
+	token := yaml_token_t{
+		typ:        typ,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+	}
+	// Append the token to the queue.
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the FLOW-SEQUENCE-START or FLOW-MAPPING-START token.
+func yaml_parser_fetch_flow_collection_start(parser *yaml_parser_t, typ yaml_token_type_t) bool {
+	// The indicators '[' and '{' may start a simple key.
+	if !yaml_parser_save_simple_key(parser) {
+		return false
+	}
+
+	// Increase the flow level.
+	if !yaml_parser_increase_flow_level(parser) {
+		return false
+	}
+
+	// A simple key may follow the indicators '[' and '{'.
+	parser.simple_key_allowed = true
+
+	// Consume the token.
+	start_mark := parser.mark
+	skip(parser)
+	end_mark := parser.mark
+
+	// Create the FLOW-SEQUENCE-START of FLOW-MAPPING-START token.
+	token := yaml_token_t{
+		typ:        typ,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+	}
+	// Append the token to the queue.
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the FLOW-SEQUENCE-END or FLOW-MAPPING-END token.
+func yaml_parser_fetch_flow_collection_end(parser *yaml_parser_t, typ yaml_token_type_t) bool {
+	// Reset any potential simple key on the current flow level.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	// Decrease the flow level.
+	if !yaml_parser_decrease_flow_level(parser) {
+		return false
+	}
+
+	// No simple keys after the indicators ']' and '}'.
+	parser.simple_key_allowed = false
+
+	// Consume the token.
+
+	start_mark := parser.mark
+	skip(parser)
+	end_mark := parser.mark
+
+	// Create the FLOW-SEQUENCE-END of FLOW-MAPPING-END token.
+	token := yaml_token_t{
+		typ:        typ,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+	}
+	// Append the token to the queue.
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the FLOW-ENTRY token.
+func yaml_parser_fetch_flow_entry(parser *yaml_parser_t) bool {
+	// Reset any potential simple keys on the current flow level.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	// Simple keys are allowed after ','.
+	parser.simple_key_allowed = true
+
+	// Consume the token.
+	start_mark := parser.mark
+	skip(parser)
+	end_mark := parser.mark
+
+	// Create the FLOW-ENTRY token and append it to the queue.
+	token := yaml_token_t{
+		typ:        yaml_FLOW_ENTRY_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the BLOCK-ENTRY token.
+func yaml_parser_fetch_block_entry(parser *yaml_parser_t) bool {
+	// Check if the scanner is in the block context.
+	if parser.flow_level == 0 {
+		// Check if we are allowed to start a new entry.
+		if !parser.simple_key_allowed {
+			return yaml_parser_set_scanner_error(parser, "", parser.mark,
+				"block sequence entries are not allowed in this context")
+		}
+		// Add the BLOCK-SEQUENCE-START token if needed.
+		if !yaml_parser_roll_indent(parser, parser.mark.column, -1, yaml_BLOCK_SEQUENCE_START_TOKEN, parser.mark) {
+			return false
+		}
+	} else {
+		// It is an error for the '-' indicator to occur in the flow context,
+		// but we let the Parser detect and report about it because the Parser
+		// is able to point to the context.
+	}
+
+	// Reset any potential simple keys on the current flow level.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	// Simple keys are allowed after '-'.
+	parser.simple_key_allowed = true
+
+	// Consume the token.
+	start_mark := parser.mark
+	skip(parser)
+	end_mark := parser.mark
+
+	// Create the BLOCK-ENTRY token and append it to the queue.
+	token := yaml_token_t{
+		typ:        yaml_BLOCK_ENTRY_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the KEY token.
+func yaml_parser_fetch_key(parser *yaml_parser_t) bool {
+
+	// In the block context, additional checks are required.
+	if parser.flow_level == 0 {
+		// Check if we are allowed to start a new key (not nessesary simple).
+		if !parser.simple_key_allowed {
+			return yaml_parser_set_scanner_error(parser, "", parser.mark,
+				"mapping keys are not allowed in this context")
+		}
+		// Add the BLOCK-MAPPING-START token if needed.
+		if !yaml_parser_roll_indent(parser, parser.mark.column, -1, yaml_BLOCK_MAPPING_START_TOKEN, parser.mark) {
+			return false
+		}
+	}
+
+	// Reset any potential simple keys on the current flow level.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	// Simple keys are allowed after '?' in the block context.
+	parser.simple_key_allowed = parser.flow_level == 0
+
+	// Consume the token.
+	start_mark := parser.mark
+	skip(parser)
+	end_mark := parser.mark
+
+	// Create the KEY token and append it to the queue.
+	token := yaml_token_t{
+		typ:        yaml_KEY_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the VALUE token.
+func yaml_parser_fetch_value(parser *yaml_parser_t) bool {
+
+	simple_key := &parser.simple_keys[len(parser.simple_keys)-1]
+
+	// Have we found a simple key?
+	if simple_key.possible {
+		// Create the KEY token and insert it into the queue.
+		token := yaml_token_t{
+			typ:        yaml_KEY_TOKEN,
+			start_mark: simple_key.mark,
+			end_mark:   simple_key.mark,
+		}
+		yaml_insert_token(parser, simple_key.token_number-parser.tokens_parsed, &token)
+
+		// In the block context, we may need to add the BLOCK-MAPPING-START token.
+		if !yaml_parser_roll_indent(parser, simple_key.mark.column,
+			simple_key.token_number,
+			yaml_BLOCK_MAPPING_START_TOKEN, simple_key.mark) {
+			return false
+		}
+
+		// Remove the simple key.
+		simple_key.possible = false
+
+		// A simple key cannot follow another simple key.
+		parser.simple_key_allowed = false
+
+	} else {
+		// The ':' indicator follows a complex key.
+
+		// In the block context, extra checks are required.
+		if parser.flow_level == 0 {
+
+			// Check if we are allowed to start a complex value.
+			if !parser.simple_key_allowed {
+				return yaml_parser_set_scanner_error(parser, "", parser.mark,
+					"mapping values are not allowed in this context")
+			}
+
+			// Add the BLOCK-MAPPING-START token if needed.
+			if !yaml_parser_roll_indent(parser, parser.mark.column, -1, yaml_BLOCK_MAPPING_START_TOKEN, parser.mark) {
+				return false
+			}
+		}
+
+		// Simple keys after ':' are allowed in the block context.
+		parser.simple_key_allowed = parser.flow_level == 0
+	}
+
+	// Consume the token.
+	start_mark := parser.mark
+	skip(parser)
+	end_mark := parser.mark
+
+	// Create the VALUE token and append it to the queue.
+	token := yaml_token_t{
+		typ:        yaml_VALUE_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the ALIAS or ANCHOR token.
+func yaml_parser_fetch_anchor(parser *yaml_parser_t, typ yaml_token_type_t) bool {
+	// An anchor or an alias could be a simple key.
+	if !yaml_parser_save_simple_key(parser) {
+		return false
+	}
+
+	// A simple key cannot follow an anchor or an alias.
+	parser.simple_key_allowed = false
+
+	// Create the ALIAS or ANCHOR token and append it to the queue.
+	var token yaml_token_t
+	if !yaml_parser_scan_anchor(parser, &token, typ) {
+		return false
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the TAG token.
+func yaml_parser_fetch_tag(parser *yaml_parser_t) bool {
+	// A tag could be a simple key.
+	if !yaml_parser_save_simple_key(parser) {
+		return false
+	}
+
+	// A simple key cannot follow a tag.
+	parser.simple_key_allowed = false
+
+	// Create the TAG token and append it to the queue.
+	var token yaml_token_t
+	if !yaml_parser_scan_tag(parser, &token) {
+		return false
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the SCALAR(...,literal) or SCALAR(...,folded) tokens.
+func yaml_parser_fetch_block_scalar(parser *yaml_parser_t, literal bool) bool {
+	// Remove any potential simple keys.
+	if !yaml_parser_remove_simple_key(parser) {
+		return false
+	}
+
+	// A simple key may follow a block scalar.
+	parser.simple_key_allowed = true
+
+	// Create the SCALAR token and append it to the queue.
+	var token yaml_token_t
+	if !yaml_parser_scan_block_scalar(parser, &token, literal) {
+		return false
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the SCALAR(...,single-quoted) or SCALAR(...,double-quoted) tokens.
+func yaml_parser_fetch_flow_scalar(parser *yaml_parser_t, single bool) bool {
+	// A plain scalar could be a simple key.
+	if !yaml_parser_save_simple_key(parser) {
+		return false
+	}
+
+	// A simple key cannot follow a flow scalar.
+	parser.simple_key_allowed = false
+
+	// Create the SCALAR token and append it to the queue.
+	var token yaml_token_t
+	if !yaml_parser_scan_flow_scalar(parser, &token, single) {
+		return false
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Produce the SCALAR(...,plain) token.
+func yaml_parser_fetch_plain_scalar(parser *yaml_parser_t) bool {
+	// A plain scalar could be a simple key.
+	if !yaml_parser_save_simple_key(parser) {
+		return false
+	}
+
+	// A simple key cannot follow a flow scalar.
+	parser.simple_key_allowed = false
+
+	// Create the SCALAR token and append it to the queue.
+	var token yaml_token_t
+	if !yaml_parser_scan_plain_scalar(parser, &token) {
+		return false
+	}
+	yaml_insert_token(parser, -1, &token)
+	return true
+}
+
+// Eat whitespaces and comments until the next token is found.
+func yaml_parser_scan_to_next_token(parser *yaml_parser_t) bool {
+
+	// Until the next token is not found.
+	for {
+		// Allow the BOM mark to start a line.
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+		if parser.mark.column == 0 && is_bom(parser.buffer, parser.buffer_pos) {
+			skip(parser)
+		}
+
+		// Eat whitespaces.
+		// Tabs are allowed:
+		//  - in the flow context
+		//  - in the block context, but not at the beginning of the line or
+		//  after '-', '?', or ':' (complex value).
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+
+		for parser.buffer[parser.buffer_pos] == ' ' || ((parser.flow_level > 0 || !parser.simple_key_allowed) && parser.buffer[parser.buffer_pos] == '\t') {
+			skip(parser)
+			if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+				return false
+			}
+		}
+
+		// Eat a comment until a line break.
+		if parser.buffer[parser.buffer_pos] == '#' {
+			for !is_breakz(parser.buffer, parser.buffer_pos) {
+				skip(parser)
+				if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+					return false
+				}
+			}
+		}
+
+		// If it is a line break, eat it.
+		if is_break(parser.buffer, parser.buffer_pos) {
+			if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+				return false
+			}
+			skip_line(parser)
+
+			// In the block context, a new line may start a simple key.
+			if parser.flow_level == 0 {
+				parser.simple_key_allowed = true
+			}
+		} else {
+			break // We have found a token.
+		}
+	}
+
+	return true
+}
+
+// Scan a YAML-DIRECTIVE or TAG-DIRECTIVE token.
+//
+// Scope:
+//      %YAML    1.1    # a comment \n
+//      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//      %TAG    !yaml!  tag:yaml.org,2002:  \n
+//      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+func yaml_parser_scan_directive(parser *yaml_parser_t, token *yaml_token_t) bool {
+	// Eat '%'.
+	start_mark := parser.mark
+	skip(parser)
+
+	// Scan the directive name.
+	var name []byte
+	if !yaml_parser_scan_directive_name(parser, start_mark, &name) {
+		return false
+	}
+
+	// Is it a YAML directive?
+	if bytes.Equal(name, []byte("YAML")) {
+		// Scan the VERSION directive value.
+		var major, minor int8
+		if !yaml_parser_scan_version_directive_value(parser, start_mark, &major, &minor) {
+			return false
+		}
+		end_mark := parser.mark
+
+		// Create a VERSION-DIRECTIVE token.
+		*token = yaml_token_t{
+			typ:        yaml_VERSION_DIRECTIVE_TOKEN,
+			start_mark: start_mark,
+			end_mark:   end_mark,
+			major:      major,
+			minor:      minor,
+		}
+
+		// Is it a TAG directive?
+	} else if bytes.Equal(name, []byte("TAG")) {
+		// Scan the TAG directive value.
+		var handle, prefix []byte
+		if !yaml_parser_scan_tag_directive_value(parser, start_mark, &handle, &prefix) {
+			return false
+		}
+		end_mark := parser.mark
+
+		// Create a TAG-DIRECTIVE token.
+		*token = yaml_token_t{
+			typ:        yaml_TAG_DIRECTIVE_TOKEN,
+			start_mark: start_mark,
+			end_mark:   end_mark,
+			value:      handle,
+			prefix:     prefix,
+		}
+
+		// Unknown directive.
+	} else {
+		yaml_parser_set_scanner_error(parser, "while scanning a directive",
+			start_mark, "found unknown directive name")
+		return false
+	}
+
+	// Eat the rest of the line including any comments.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+
+	for is_blank(parser.buffer, parser.buffer_pos) {
+		skip(parser)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	if parser.buffer[parser.buffer_pos] == '#' {
+		for !is_breakz(parser.buffer, parser.buffer_pos) {
+			skip(parser)
+			if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+				return false
+			}
+		}
+	}
+
+	// Check if we are at the end of the line.
+	if !is_breakz(parser.buffer, parser.buffer_pos) {
+		yaml_parser_set_scanner_error(parser, "while scanning a directive",
+			start_mark, "did not find expected comment or line break")
+		return false
+	}
+
+	// Eat a line break.
+	if is_break(parser.buffer, parser.buffer_pos) {
+		if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+			return false
+		}
+		skip_line(parser)
+	}
+
+	return true
+}
+
+// Scan the directive name.
+//
+// Scope:
+//      %YAML   1.1     # a comment \n
+//       ^^^^
+//      %TAG    !yaml!  tag:yaml.org,2002:  \n
+//       ^^^
+//
+func yaml_parser_scan_directive_name(parser *yaml_parser_t, start_mark yaml_mark_t, name *[]byte) bool {
+	// Consume the directive name.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+
+	var s []byte
+	for is_alpha(parser.buffer, parser.buffer_pos) {
+		s = read(parser, s)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	// Check if the name is empty.
+	if len(s) == 0 {
+		yaml_parser_set_scanner_error(parser, "while scanning a directive",
+			start_mark, "could not find expected directive name")
+		return false
+	}
+
+	// Check for an blank character after the name.
+	if !is_blankz(parser.buffer, parser.buffer_pos) {
+		yaml_parser_set_scanner_error(parser, "while scanning a directive",
+			start_mark, "found unexpected non-alphabetical character")
+		return false
+	}
+	*name = s
+	return true
+}
+
+// Scan the value of VERSION-DIRECTIVE.
+//
+// Scope:
+//      %YAML   1.1     # a comment \n
+//           ^^^^^^
+func yaml_parser_scan_version_directive_value(parser *yaml_parser_t, start_mark yaml_mark_t, major, minor *int8) bool {
+	// Eat whitespaces.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	for is_blank(parser.buffer, parser.buffer_pos) {
+		skip(parser)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	// Consume the major version number.
+	if !yaml_parser_scan_version_directive_number(parser, start_mark, major) {
+		return false
+	}
+
+	// Eat '.'.
+	if parser.buffer[parser.buffer_pos] != '.' {
+		return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
+			start_mark, "did not find expected digit or '.' character")
+	}
+
+	skip(parser)
+
+	// Consume the minor version number.
+	if !yaml_parser_scan_version_directive_number(parser, start_mark, minor) {
+		return false
+	}
+	return true
+}
+
+const max_number_length = 2
+
+// Scan the version number of VERSION-DIRECTIVE.
+//
+// Scope:
+//      %YAML   1.1     # a comment \n
+//              ^
+//      %YAML   1.1     # a comment \n
+//                ^
+func yaml_parser_scan_version_directive_number(parser *yaml_parser_t, start_mark yaml_mark_t, number *int8) bool {
+
+	// Repeat while the next character is digit.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	var value, length int8
+	for is_digit(parser.buffer, parser.buffer_pos) {
+		// Check if the number is too long.
+		length++
+		if length > max_number_length {
+			return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
+				start_mark, "found extremely long version number")
+		}
+		value = value*10 + int8(as_digit(parser.buffer, parser.buffer_pos))
+		skip(parser)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	// Check if the number was present.
+	if length == 0 {
+		return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
+			start_mark, "did not find expected version number")
+	}
+	*number = value
+	return true
+}
+
+// Scan the value of a TAG-DIRECTIVE token.
+//
+// Scope:
+//      %TAG    !yaml!  tag:yaml.org,2002:  \n
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+func yaml_parser_scan_tag_directive_value(parser *yaml_parser_t, start_mark yaml_mark_t, handle, prefix *[]byte) bool {
+	var handle_value, prefix_value []byte
+
+	// Eat whitespaces.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+
+	for is_blank(parser.buffer, parser.buffer_pos) {
+		skip(parser)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	// Scan a handle.
+	if !yaml_parser_scan_tag_handle(parser, true, start_mark, &handle_value) {
+		return false
+	}
+
+	// Expect a whitespace.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	if !is_blank(parser.buffer, parser.buffer_pos) {
+		yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive",
+			start_mark, "did not find expected whitespace")
+		return false
+	}
+
+	// Eat whitespaces.
+	for is_blank(parser.buffer, parser.buffer_pos) {
+		skip(parser)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	// Scan a prefix.
+	if !yaml_parser_scan_tag_uri(parser, true, nil, start_mark, &prefix_value) {
+		return false
+	}
+
+	// Expect a whitespace or line break.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	if !is_blankz(parser.buffer, parser.buffer_pos) {
+		yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive",
+			start_mark, "did not find expected whitespace or line break")
+		return false
+	}
+
+	*handle = handle_value
+	*prefix = prefix_value
+	return true
+}
+
+func yaml_parser_scan_anchor(parser *yaml_parser_t, token *yaml_token_t, typ yaml_token_type_t) bool {
+	var s []byte
+
+	// Eat the indicator character.
+	start_mark := parser.mark
+	skip(parser)
+
+	// Consume the value.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+
+	for is_alpha(parser.buffer, parser.buffer_pos) {
+		s = read(parser, s)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	end_mark := parser.mark
+
+	/*
+	 * Check if length of the anchor is greater than 0 and it is followed by
+	 * a whitespace character or one of the indicators:
+	 *
+	 *      '?', ':', ',', ']', '}', '%', '@', '`'.
+	 */
+
+	if len(s) == 0 ||
+		!(is_blankz(parser.buffer, parser.buffer_pos) || parser.buffer[parser.buffer_pos] == '?' ||
+			parser.buffer[parser.buffer_pos] == ':' || parser.buffer[parser.buffer_pos] == ',' ||
+			parser.buffer[parser.buffer_pos] == ']' || parser.buffer[parser.buffer_pos] == '}' ||
+			parser.buffer[parser.buffer_pos] == '%' || parser.buffer[parser.buffer_pos] == '@' ||
+			parser.buffer[parser.buffer_pos] == '`') {
+		context := "while scanning an alias"
+		if typ == yaml_ANCHOR_TOKEN {
+			context = "while scanning an anchor"
+		}
+		yaml_parser_set_scanner_error(parser, context, start_mark,
+			"did not find expected alphabetic or numeric character")
+		return false
+	}
+
+	// Create a token.
+	*token = yaml_token_t{
+		typ:        typ,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+		value:      s,
+	}
+
+	return true
+}
+
+/*
+ * Scan a TAG token.
+ */
+
+func yaml_parser_scan_tag(parser *yaml_parser_t, token *yaml_token_t) bool {
+	var handle, suffix []byte
+
+	start_mark := parser.mark
+
+	// Check if the tag is in the canonical form.
+	if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+		return false
+	}
+
+	if parser.buffer[parser.buffer_pos+1] == '<' {
+		// Keep the handle as ''
+
+		// Eat '!<'
+		skip(parser)
+		skip(parser)
+
+		// Consume the tag value.
+		if !yaml_parser_scan_tag_uri(parser, false, nil, start_mark, &suffix) {
+			return false
+		}
+
+		// Check for '>' and eat it.
+		if parser.buffer[parser.buffer_pos] != '>' {
+			yaml_parser_set_scanner_error(parser, "while scanning a tag",
+				start_mark, "did not find the expected '>'")
+			return false
+		}
+
+		skip(parser)
+	} else {
+		// The tag has either the '!suffix' or the '!handle!suffix' form.
+
+		// First, try to scan a handle.
+		if !yaml_parser_scan_tag_handle(parser, false, start_mark, &handle) {
+			return false
+		}
+
+		// Check if it is, indeed, handle.
+		if handle[0] == '!' && len(handle) > 1 && handle[len(handle)-1] == '!' {
+			// Scan the suffix now.
+			if !yaml_parser_scan_tag_uri(parser, false, nil, start_mark, &suffix) {
+				return false
+			}
+		} else {
+			// It wasn't a handle after all.  Scan the rest of the tag.
+			if !yaml_parser_scan_tag_uri(parser, false, handle, start_mark, &suffix) {
+				return false
+			}
+
+			// Set the handle to '!'.
+			handle = []byte{'!'}
+
+			// A special case: the '!' tag.  Set the handle to '' and the
+			// suffix to '!'.
+			if len(suffix) == 0 {
+				handle, suffix = suffix, handle
+			}
+		}
+	}
+
+	// Check the character which ends the tag.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	if !is_blankz(parser.buffer, parser.buffer_pos) {
+		yaml_parser_set_scanner_error(parser, "while scanning a tag",
+			start_mark, "did not find expected whitespace or line break")
+		return false
+	}
+
+	end_mark := parser.mark
+
+	// Create a token.
+	*token = yaml_token_t{
+		typ:        yaml_TAG_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+		value:      handle,
+		suffix:     suffix,
+	}
+	return true
+}
+
+// Scan a tag handle.
+func yaml_parser_scan_tag_handle(parser *yaml_parser_t, directive bool, start_mark yaml_mark_t, handle *[]byte) bool {
+	// Check the initial '!' character.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	if parser.buffer[parser.buffer_pos] != '!' {
+		yaml_parser_set_scanner_tag_error(parser, directive,
+			start_mark, "did not find expected '!'")
+		return false
+	}
+
+	var s []byte
+
+	// Copy the '!' character.
+	s = read(parser, s)
+
+	// Copy all subsequent alphabetical and numerical characters.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	for is_alpha(parser.buffer, parser.buffer_pos) {
+		s = read(parser, s)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	// Check if the trailing character is '!' and copy it.
+	if parser.buffer[parser.buffer_pos] == '!' {
+		s = read(parser, s)
+	} else {
+		// It's either the '!' tag or not really a tag handle.  If it's a %TAG
+		// directive, it's an error.  If it's a tag token, it must be a part of URI.
+		if directive && !(s[0] == '!' && s[1] == 0) {
+			yaml_parser_set_scanner_tag_error(parser, directive,
+				start_mark, "did not find expected '!'")
+			return false
+		}
+	}
+
+	*handle = s
+	return true
+}
+
+// Scan a tag.
+func yaml_parser_scan_tag_uri(parser *yaml_parser_t, directive bool, head []byte, start_mark yaml_mark_t, uri *[]byte) bool {
+	//size_t length = head ? strlen((char *)head) : 0
+	var s []byte
+
+	// Copy the head if needed.
+	//
+	// Note that we don't copy the leading '!' character.
+	if len(head) > 1 {
+		s = append(s, head[1:]...)
+	}
+
+	// Scan the tag.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+
+	// The set of characters that may appear in URI is as follows:
+	//
+	//      '0'-'9', 'A'-'Z', 'a'-'z', '_', '-', ';', '/', '?', ':', '@', '&',
+	//      '=', '+', '$', ',', '.', '!', '~', '*', '\'', '(', ')', '[', ']',
+	//      '%'.
+	// [Go] Convert this into more reasonable logic.
+	for is_alpha(parser.buffer, parser.buffer_pos) || parser.buffer[parser.buffer_pos] == ';' ||
+		parser.buffer[parser.buffer_pos] == '/' || parser.buffer[parser.buffer_pos] == '?' ||
+		parser.buffer[parser.buffer_pos] == ':' || parser.buffer[parser.buffer_pos] == '@' ||
+		parser.buffer[parser.buffer_pos] == '&' || parser.buffer[parser.buffer_pos] == '=' ||
+		parser.buffer[parser.buffer_pos] == '+' || parser.buffer[parser.buffer_pos] == '$' ||
+		parser.buffer[parser.buffer_pos] == ',' || parser.buffer[parser.buffer_pos] == '.' ||
+		parser.buffer[parser.buffer_pos] == '!' || parser.buffer[parser.buffer_pos] == '~' ||
+		parser.buffer[parser.buffer_pos] == '*' || parser.buffer[parser.buffer_pos] == '\'' ||
+		parser.buffer[parser.buffer_pos] == '(' || parser.buffer[parser.buffer_pos] == ')' ||
+		parser.buffer[parser.buffer_pos] == '[' || parser.buffer[parser.buffer_pos] == ']' ||
+		parser.buffer[parser.buffer_pos] == '%' {
+		// Check if it is a URI-escape sequence.
+		if parser.buffer[parser.buffer_pos] == '%' {
+			if !yaml_parser_scan_uri_escapes(parser, directive, start_mark, &s) {
+				return false
+			}
+		} else {
+			s = read(parser, s)
+		}
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+
+	// Check if the tag is non-empty.
+	if len(s) == 0 {
+		yaml_parser_set_scanner_tag_error(parser, directive,
+			start_mark, "did not find expected tag URI")
+		return false
+	}
+	*uri = s
+	return true
+}
+
+// Decode an URI-escape sequence corresponding to a single UTF-8 character.
+func yaml_parser_scan_uri_escapes(parser *yaml_parser_t, directive bool, start_mark yaml_mark_t, s *[]byte) bool {
+
+	// Decode the required number of characters.
+	w := 1024
+	for w > 0 {
+		// Check for a URI-escaped octet.
+		if parser.unread < 3 && !yaml_parser_update_buffer(parser, 3) {
+			return false
+		}
+
+		if !(parser.buffer[parser.buffer_pos] == '%' &&
+			is_hex(parser.buffer, parser.buffer_pos+1) &&
+			is_hex(parser.buffer, parser.buffer_pos+2)) {
+			return yaml_parser_set_scanner_tag_error(parser, directive,
+				start_mark, "did not find URI escaped octet")
+		}
+
+		// Get the octet.
+		octet := byte((as_hex(parser.buffer, parser.buffer_pos+1) << 4) + as_hex(parser.buffer, parser.buffer_pos+2))
+
+		// If it is the leading octet, determine the length of the UTF-8 sequence.
+		if w == 1024 {
+			w = width(octet)
+			if w == 0 {
+				return yaml_parser_set_scanner_tag_error(parser, directive,
+					start_mark, "found an incorrect leading UTF-8 octet")
+			}
+		} else {
+			// Check if the trailing octet is correct.
+			if octet&0xC0 != 0x80 {
+				return yaml_parser_set_scanner_tag_error(parser, directive,
+					start_mark, "found an incorrect trailing UTF-8 octet")
+			}
+		}
+
+		// Copy the octet and move the pointers.
+		*s = append(*s, octet)
+		skip(parser)
+		skip(parser)
+		skip(parser)
+		w--
+	}
+	return true
+}
+
+// Scan a block scalar.
+func yaml_parser_scan_block_scalar(parser *yaml_parser_t, token *yaml_token_t, literal bool) bool {
+	// Eat the indicator '|' or '>'.
+	start_mark := parser.mark
+	skip(parser)
+
+	// Scan the additional block scalar indicators.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+
+	// Check for a chomping indicator.
+	var chomping, increment int
+	if parser.buffer[parser.buffer_pos] == '+' || parser.buffer[parser.buffer_pos] == '-' {
+		// Set the chomping method and eat the indicator.
+		if parser.buffer[parser.buffer_pos] == '+' {
+			chomping = +1
+		} else {
+			chomping = -1
+		}
+		skip(parser)
+
+		// Check for an indentation indicator.
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+		if is_digit(parser.buffer, parser.buffer_pos) {
+			// Check that the indentation is greater than 0.
+			if parser.buffer[parser.buffer_pos] == '0' {
+				yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
+					start_mark, "found an indentation indicator equal to 0")
+				return false
+			}
+
+			// Get the indentation level and eat the indicator.
+			increment = as_digit(parser.buffer, parser.buffer_pos)
+			skip(parser)
+		}
+
+	} else if is_digit(parser.buffer, parser.buffer_pos) {
+		// Do the same as above, but in the opposite order.
+
+		if parser.buffer[parser.buffer_pos] == '0' {
+			yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
+				start_mark, "found an indentation indicator equal to 0")
+			return false
+		}
+		increment = as_digit(parser.buffer, parser.buffer_pos)
+		skip(parser)
+
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+		if parser.buffer[parser.buffer_pos] == '+' || parser.buffer[parser.buffer_pos] == '-' {
+			if parser.buffer[parser.buffer_pos] == '+' {
+				chomping = +1
+			} else {
+				chomping = -1
+			}
+			skip(parser)
+		}
+	}
+
+	// Eat whitespaces and comments to the end of the line.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	for is_blank(parser.buffer, parser.buffer_pos) {
+		skip(parser)
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+	}
+	if parser.buffer[parser.buffer_pos] == '#' {
+		for !is_breakz(parser.buffer, parser.buffer_pos) {
+			skip(parser)
+			if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+				return false
+			}
+		}
+	}
+
+	// Check if we are at the end of the line.
+	if !is_breakz(parser.buffer, parser.buffer_pos) {
+		yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
+			start_mark, "did not find expected comment or line break")
+		return false
+	}
+
+	// Eat a line break.
+	if is_break(parser.buffer, parser.buffer_pos) {
+		if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+			return false
+		}
+		skip_line(parser)
+	}
+
+	end_mark := parser.mark
+
+	// Set the indentation level if it was specified.
+	var indent int
+	if increment > 0 {
+		if parser.indent >= 0 {
+			indent = parser.indent + increment
+		} else {
+			indent = increment
+		}
+	}
+
+	// Scan the leading line breaks and determine the indentation level if needed.
+	var s, leading_break, trailing_breaks []byte
+	if !yaml_parser_scan_block_scalar_breaks(parser, &indent, &trailing_breaks, start_mark, &end_mark) {
+		return false
+	}
+
+	// Scan the block scalar content.
+	if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+		return false
+	}
+	var leading_blank, trailing_blank bool
+	for parser.mark.column == indent && !is_z(parser.buffer, parser.buffer_pos) {
+		// We are at the beginning of a non-empty line.
+
+		// Is it a trailing whitespace?
+		trailing_blank = is_blank(parser.buffer, parser.buffer_pos)
+
+		// Check if we need to fold the leading line break.
+		if !literal && !leading_blank && !trailing_blank && len(leading_break) > 0 && leading_break[0] == '\n' {
+			// Do we need to join the lines by space?
+			if len(trailing_breaks) == 0 {
+				s = append(s, ' ')
+			}
+		} else {
+			s = append(s, leading_break...)
+		}
+		leading_break = leading_break[:0]
+
+		// Append the remaining line breaks.
+		s = append(s, trailing_breaks...)
+		trailing_breaks = trailing_breaks[:0]
+
+		// Is it a leading whitespace?
+		leading_blank = is_blank(parser.buffer, parser.buffer_pos)
+
+		// Consume the current line.
+		for !is_breakz(parser.buffer, parser.buffer_pos) {
+			s = read(parser, s)
+			if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+				return false
+			}
+		}
+
+		// Consume the line break.
+		if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+			return false
+		}
+
+		leading_break = read_line(parser, leading_break)
+
+		// Eat the following indentation spaces and line breaks.
+		if !yaml_parser_scan_block_scalar_breaks(parser, &indent, &trailing_breaks, start_mark, &end_mark) {
+			return false
+		}
+	}
+
+	// Chomp the tail.
+	if chomping != -1 {
+		s = append(s, leading_break...)
+	}
+	if chomping == 1 {
+		s = append(s, trailing_breaks...)
+	}
+
+	// Create a token.
+	*token = yaml_token_t{
+		typ:        yaml_SCALAR_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+		value:      s,
+		style:      yaml_LITERAL_SCALAR_STYLE,
+	}
+	if !literal {
+		token.style = yaml_FOLDED_SCALAR_STYLE
+	}
+	return true
+}
+
+// Scan indentation spaces and line breaks for a block scalar.  Determine the
+// indentation level if needed.
+func yaml_parser_scan_block_scalar_breaks(parser *yaml_parser_t, indent *int, breaks *[]byte, start_mark yaml_mark_t, end_mark *yaml_mark_t) bool {
+	*end_mark = parser.mark
+
+	// Eat the indentation spaces and line breaks.
+	max_indent := 0
+	for {
+		// Eat the indentation spaces.
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+		for (*indent == 0 || parser.mark.column < *indent) && is_space(parser.buffer, parser.buffer_pos) {
+			skip(parser)
+			if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+				return false
+			}
+		}
+		if parser.mark.column > max_indent {
+			max_indent = parser.mark.column
+		}
+
+		// Check for a tab character messing the indentation.
+		if (*indent == 0 || parser.mark.column < *indent) && is_tab(parser.buffer, parser.buffer_pos) {
+			return yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
+				start_mark, "found a tab character where an indentation space is expected")
+		}
+
+		// Have we found a non-empty line?
+		if !is_break(parser.buffer, parser.buffer_pos) {
+			break
+		}
+
+		// Consume the line break.
+		if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+			return false
+		}
+		// [Go] Should really be returning breaks instead.
+		*breaks = read_line(parser, *breaks)
+		*end_mark = parser.mark
+	}
+
+	// Determine the indentation level if needed.
+	if *indent == 0 {
+		*indent = max_indent
+		if *indent < parser.indent+1 {
+			*indent = parser.indent + 1
+		}
+		if *indent < 1 {
+			*indent = 1
+		}
+	}
+	return true
+}
+
+// Scan a quoted scalar.
+func yaml_parser_scan_flow_scalar(parser *yaml_parser_t, token *yaml_token_t, single bool) bool {
+	// Eat the left quote.
+	start_mark := parser.mark
+	skip(parser)
+
+	// Consume the content of the quoted scalar.
+	var s, leading_break, trailing_breaks, whitespaces []byte
+	for {
+		// Check that there are no document indicators at the beginning of the line.
+		if parser.unread < 4 && !yaml_parser_update_buffer(parser, 4) {
+			return false
+		}
+
+		if parser.mark.column == 0 &&
+			((parser.buffer[parser.buffer_pos+0] == '-' &&
+				parser.buffer[parser.buffer_pos+1] == '-' &&
+				parser.buffer[parser.buffer_pos+2] == '-') ||
+				(parser.buffer[parser.buffer_pos+0] == '.' &&
+					parser.buffer[parser.buffer_pos+1] == '.' &&
+					parser.buffer[parser.buffer_pos+2] == '.')) &&
+			is_blankz(parser.buffer, parser.buffer_pos+3) {
+			yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar",
+				start_mark, "found unexpected document indicator")
+			return false
+		}
+
+		// Check for EOF.
+		if is_z(parser.buffer, parser.buffer_pos) {
+			yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar",
+				start_mark, "found unexpected end of stream")
+			return false
+		}
+
+		// Consume non-blank characters.
+		leading_blanks := false
+		for !is_blankz(parser.buffer, parser.buffer_pos) {
+			if single && parser.buffer[parser.buffer_pos] == '\'' && parser.buffer[parser.buffer_pos+1] == '\'' {
+				// Is is an escaped single quote.
+				s = append(s, '\'')
+				skip(parser)
+				skip(parser)
+
+			} else if single && parser.buffer[parser.buffer_pos] == '\'' {
+				// It is a right single quote.
+				break
+			} else if !single && parser.buffer[parser.buffer_pos] == '"' {
+				// It is a right double quote.
+				break
+
+			} else if !single && parser.buffer[parser.buffer_pos] == '\\' && is_break(parser.buffer, parser.buffer_pos+1) {
+				// It is an escaped line break.
+				if parser.unread < 3 && !yaml_parser_update_buffer(parser, 3) {
+					return false
+				}
+				skip(parser)
+				skip_line(parser)
+				leading_blanks = true
+				break
+
+			} else if !single && parser.buffer[parser.buffer_pos] == '\\' {
+				// It is an escape sequence.
+				code_length := 0
+
+				// Check the escape character.
+				switch parser.buffer[parser.buffer_pos+1] {
+				case '0':
+					s = append(s, 0)
+				case 'a':
+					s = append(s, '\x07')
+				case 'b':
+					s = append(s, '\x08')
+				case 't', '\t':
+					s = append(s, '\x09')
+				case 'n':
+					s = append(s, '\x0A')
+				case 'v':
+					s = append(s, '\x0B')
+				case 'f':
+					s = append(s, '\x0C')
+				case 'r':
+					s = append(s, '\x0D')
+				case 'e':
+					s = append(s, '\x1B')
+				case ' ':
+					s = append(s, '\x20')
+				case '"':
+					s = append(s, '"')
+				case '\'':
+					s = append(s, '\'')
+				case '\\':
+					s = append(s, '\\')
+				case 'N': // NEL (#x85)
+					s = append(s, '\xC2')
+					s = append(s, '\x85')
+				case '_': // #xA0
+					s = append(s, '\xC2')
+					s = append(s, '\xA0')
+				case 'L': // LS (#x2028)
+					s = append(s, '\xE2')
+					s = append(s, '\x80')
+					s = append(s, '\xA8')
+				case 'P': // PS (#x2029)
+					s = append(s, '\xE2')
+					s = append(s, '\x80')
+					s = append(s, '\xA9')
+				case 'x':
+					code_length = 2
+				case 'u':
+					code_length = 4
+				case 'U':
+					code_length = 8
+				default:
+					yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
+						start_mark, "found unknown escape character")
+					return false
+				}
+
+				skip(parser)
+				skip(parser)
+
+				// Consume an arbitrary escape code.
+				if code_length > 0 {
+					var value int
+
+					// Scan the character value.
+					if parser.unread < code_length && !yaml_parser_update_buffer(parser, code_length) {
+						return false
+					}
+					for k := 0; k < code_length; k++ {
+						if !is_hex(parser.buffer, parser.buffer_pos+k) {
+							yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
+								start_mark, "did not find expected hexdecimal number")
+							return false
+						}
+						value = (value << 4) + as_hex(parser.buffer, parser.buffer_pos+k)
+					}
+
+					// Check the value and write the character.
+					if (value >= 0xD800 && value <= 0xDFFF) || value > 0x10FFFF {
+						yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
+							start_mark, "found invalid Unicode character escape code")
+						return false
+					}
+					if value <= 0x7F {
+						s = append(s, byte(value))
+					} else if value <= 0x7FF {
+						s = append(s, byte(0xC0+(value>>6)))
+						s = append(s, byte(0x80+(value&0x3F)))
+					} else if value <= 0xFFFF {
+						s = append(s, byte(0xE0+(value>>12)))
+						s = append(s, byte(0x80+((value>>6)&0x3F)))
+						s = append(s, byte(0x80+(value&0x3F)))
+					} else {
+						s = append(s, byte(0xF0+(value>>18)))
+						s = append(s, byte(0x80+((value>>12)&0x3F)))
+						s = append(s, byte(0x80+((value>>6)&0x3F)))
+						s = append(s, byte(0x80+(value&0x3F)))
+					}
+
+					// Advance the pointer.
+					for k := 0; k < code_length; k++ {
+						skip(parser)
+					}
+				}
+			} else {
+				// It is a non-escaped non-blank character.
+				s = read(parser, s)
+			}
+			if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+				return false
+			}
+		}
+
+		// Check if we are at the end of the scalar.
+		if single {
+			if parser.buffer[parser.buffer_pos] == '\'' {
+				break
+			}
+		} else {
+			if parser.buffer[parser.buffer_pos] == '"' {
+				break
+			}
+		}
+
+		// Consume blank characters.
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+
+		for is_blank(parser.buffer, parser.buffer_pos) || is_break(parser.buffer, parser.buffer_pos) {
+			if is_blank(parser.buffer, parser.buffer_pos) {
+				// Consume a space or a tab character.
+				if !leading_blanks {
+					whitespaces = read(parser, whitespaces)
+				} else {
+					skip(parser)
+				}
+			} else {
+				if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+					return false
+				}
+
+				// Check if it is a first line break.
+				if !leading_blanks {
+					whitespaces = whitespaces[:0]
+					leading_break = read_line(parser, leading_break)
+					leading_blanks = true
+				} else {
+					trailing_breaks = read_line(parser, trailing_breaks)
+				}
+			}
+			if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+				return false
+			}
+		}
+
+		// Join the whitespaces or fold line breaks.
+		if leading_blanks {
+			// Do we need to fold line breaks?
+			if len(leading_break) > 0 && leading_break[0] == '\n' {
+				if len(trailing_breaks) == 0 {
+					s = append(s, ' ')
+				} else {
+					s = append(s, trailing_breaks...)
+				}
+			} else {
+				s = append(s, leading_break...)
+				s = append(s, trailing_breaks...)
+			}
+			trailing_breaks = trailing_breaks[:0]
+			leading_break = leading_break[:0]
+		} else {
+			s = append(s, whitespaces...)
+			whitespaces = whitespaces[:0]
+		}
+	}
+
+	// Eat the right quote.
+	skip(parser)
+	end_mark := parser.mark
+
+	// Create a token.
+	*token = yaml_token_t{
+		typ:        yaml_SCALAR_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+		value:      s,
+		style:      yaml_SINGLE_QUOTED_SCALAR_STYLE,
+	}
+	if !single {
+		token.style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+	}
+	return true
+}
+
+// Scan a plain scalar.
+func yaml_parser_scan_plain_scalar(parser *yaml_parser_t, token *yaml_token_t) bool {
+
+	var s, leading_break, trailing_breaks, whitespaces []byte
+	var leading_blanks bool
+	var indent = parser.indent + 1
+
+	start_mark := parser.mark
+	end_mark := parser.mark
+
+	// Consume the content of the plain scalar.
+	for {
+		// Check for a document indicator.
+		if parser.unread < 4 && !yaml_parser_update_buffer(parser, 4) {
+			return false
+		}
+		if parser.mark.column == 0 &&
+			((parser.buffer[parser.buffer_pos+0] == '-' &&
+				parser.buffer[parser.buffer_pos+1] == '-' &&
+				parser.buffer[parser.buffer_pos+2] == '-') ||
+				(parser.buffer[parser.buffer_pos+0] == '.' &&
+					parser.buffer[parser.buffer_pos+1] == '.' &&
+					parser.buffer[parser.buffer_pos+2] == '.')) &&
+			is_blankz(parser.buffer, parser.buffer_pos+3) {
+			break
+		}
+
+		// Check for a comment.
+		if parser.buffer[parser.buffer_pos] == '#' {
+			break
+		}
+
+		// Consume non-blank characters.
+		for !is_blankz(parser.buffer, parser.buffer_pos) {
+
+			// Check for 'x:x' in the flow context. TODO: Fix the test "spec-08-13".
+			if parser.flow_level > 0 &&
+				parser.buffer[parser.buffer_pos] == ':' &&
+				!is_blankz(parser.buffer, parser.buffer_pos+1) {
+				yaml_parser_set_scanner_error(parser, "while scanning a plain scalar",
+					start_mark, "found unexpected ':'")
+				return false
+			}
+
+			// Check for indicators that may end a plain scalar.
+			if (parser.buffer[parser.buffer_pos] == ':' && is_blankz(parser.buffer, parser.buffer_pos+1)) ||
+				(parser.flow_level > 0 &&
+					(parser.buffer[parser.buffer_pos] == ',' || parser.buffer[parser.buffer_pos] == ':' ||
+						parser.buffer[parser.buffer_pos] == '?' || parser.buffer[parser.buffer_pos] == '[' ||
+						parser.buffer[parser.buffer_pos] == ']' || parser.buffer[parser.buffer_pos] == '{' ||
+						parser.buffer[parser.buffer_pos] == '}')) {
+				break
+			}
+
+			// Check if we need to join whitespaces and breaks.
+			if leading_blanks || len(whitespaces) > 0 {
+				if leading_blanks {
+					// Do we need to fold line breaks?
+					if leading_break[0] == '\n' {
+						if len(trailing_breaks) == 0 {
+							s = append(s, ' ')
+						} else {
+							s = append(s, trailing_breaks...)
+						}
+					} else {
+						s = append(s, leading_break...)
+						s = append(s, trailing_breaks...)
+					}
+					trailing_breaks = trailing_breaks[:0]
+					leading_break = leading_break[:0]
+					leading_blanks = false
+				} else {
+					s = append(s, whitespaces...)
+					whitespaces = whitespaces[:0]
+				}
+			}
+
+			// Copy the character.
+			s = read(parser, s)
+
+			end_mark = parser.mark
+			if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+				return false
+			}
+		}
+
+		// Is it the end?
+		if !(is_blank(parser.buffer, parser.buffer_pos) || is_break(parser.buffer, parser.buffer_pos)) {
+			break
+		}
+
+		// Consume blank characters.
+		if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+			return false
+		}
+
+		for is_blank(parser.buffer, parser.buffer_pos) || is_break(parser.buffer, parser.buffer_pos) {
+			if is_blank(parser.buffer, parser.buffer_pos) {
+
+				// Check for tab character that abuse indentation.
+				if leading_blanks && parser.mark.column < indent && is_tab(parser.buffer, parser.buffer_pos) {
+					yaml_parser_set_scanner_error(parser, "while scanning a plain scalar",
+						start_mark, "found a tab character that violate indentation")
+					return false
+				}
+
+				// Consume a space or a tab character.
+				if !leading_blanks {
+					whitespaces = read(parser, whitespaces)
+				} else {
+					skip(parser)
+				}
+			} else {
+				if parser.unread < 2 && !yaml_parser_update_buffer(parser, 2) {
+					return false
+				}
+
+				// Check if it is a first line break.
+				if !leading_blanks {
+					whitespaces = whitespaces[:0]
+					leading_break = read_line(parser, leading_break)
+					leading_blanks = true
+				} else {
+					trailing_breaks = read_line(parser, trailing_breaks)
+				}
+			}
+			if parser.unread < 1 && !yaml_parser_update_buffer(parser, 1) {
+				return false
+			}
+		}
+
+		// Check indentation level.
+		if parser.flow_level == 0 && parser.mark.column < indent {
+			break
+		}
+	}
+
+	// Create a token.
+	*token = yaml_token_t{
+		typ:        yaml_SCALAR_TOKEN,
+		start_mark: start_mark,
+		end_mark:   end_mark,
+		value:      s,
+		style:      yaml_PLAIN_SCALAR_STYLE,
+	}
+
+	// Note that we change the 'simple_key_allowed' flag.
+	if leading_blanks {
+		parser.simple_key_allowed = true
+	}
+	return true
+}
diff --git a/vendor/gopkg.in/yaml.v2/sorter.go b/vendor/gopkg.in/yaml.v2/sorter.go
new file mode 100644
index 000000000..5958822f9
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/sorter.go
@@ -0,0 +1,104 @@
+package yaml
+
+import (
+	"reflect"
+	"unicode"
+)
+
+type keyList []reflect.Value
+
+func (l keyList) Len() int      { return len(l) }
+func (l keyList) Swap(i, j int) { l[i], l[j] = l[j], l[i] }
+func (l keyList) Less(i, j int) bool {
+	a := l[i]
+	b := l[j]
+	ak := a.Kind()
+	bk := b.Kind()
+	for (ak == reflect.Interface || ak == reflect.Ptr) && !a.IsNil() {
+		a = a.Elem()
+		ak = a.Kind()
+	}
+	for (bk == reflect.Interface || bk == reflect.Ptr) && !b.IsNil() {
+		b = b.Elem()
+		bk = b.Kind()
+	}
+	af, aok := keyFloat(a)
+	bf, bok := keyFloat(b)
+	if aok && bok {
+		if af != bf {
+			return af < bf
+		}
+		if ak != bk {
+			return ak < bk
+		}
+		return numLess(a, b)
+	}
+	if ak != reflect.String || bk != reflect.String {
+		return ak < bk
+	}
+	ar, br := []rune(a.String()), []rune(b.String())
+	for i := 0; i < len(ar) && i < len(br); i++ {
+		if ar[i] == br[i] {
+			continue
+		}
+		al := unicode.IsLetter(ar[i])
+		bl := unicode.IsLetter(br[i])
+		if al && bl {
+			return ar[i] < br[i]
+		}
+		if al || bl {
+			return bl
+		}
+		var ai, bi int
+		var an, bn int64
+		for ai = i; ai < len(ar) && unicode.IsDigit(ar[ai]); ai++ {
+			an = an*10 + int64(ar[ai]-'0')
+		}
+		for bi = i; bi < len(br) && unicode.IsDigit(br[bi]); bi++ {
+			bn = bn*10 + int64(br[bi]-'0')
+		}
+		if an != bn {
+			return an < bn
+		}
+		if ai != bi {
+			return ai < bi
+		}
+		return ar[i] < br[i]
+	}
+	return len(ar) < len(br)
+}
+
+// keyFloat returns a float value for v if it is a number/bool
+// and whether it is a number/bool or not.
+func keyFloat(v reflect.Value) (f float64, ok bool) {
+	switch v.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return float64(v.Int()), true
+	case reflect.Float32, reflect.Float64:
+		return v.Float(), true
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return float64(v.Uint()), true
+	case reflect.Bool:
+		if v.Bool() {
+			return 1, true
+		}
+		return 0, true
+	}
+	return 0, false
+}
+
+// numLess returns whether a < b.
+// a and b must necessarily have the same kind.
+func numLess(a, b reflect.Value) bool {
+	switch a.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return a.Int() < b.Int()
+	case reflect.Float32, reflect.Float64:
+		return a.Float() < b.Float()
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return a.Uint() < b.Uint()
+	case reflect.Bool:
+		return !a.Bool() && b.Bool()
+	}
+	panic("not a number")
+}
diff --git a/vendor/gopkg.in/yaml.v2/writerc.go b/vendor/gopkg.in/yaml.v2/writerc.go
new file mode 100644
index 000000000..190362f25
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/writerc.go
@@ -0,0 +1,89 @@
+package yaml
+
+// Set the writer error and return false.
+func yaml_emitter_set_writer_error(emitter *yaml_emitter_t, problem string) bool {
+	emitter.error = yaml_WRITER_ERROR
+	emitter.problem = problem
+	return false
+}
+
+// Flush the output buffer.
+func yaml_emitter_flush(emitter *yaml_emitter_t) bool {
+	if emitter.write_handler == nil {
+		panic("write handler not set")
+	}
+
+	// Check if the buffer is empty.
+	if emitter.buffer_pos == 0 {
+		return true
+	}
+
+	// If the output encoding is UTF-8, we don't need to recode the buffer.
+	if emitter.encoding == yaml_UTF8_ENCODING {
+		if err := emitter.write_handler(emitter, emitter.buffer[:emitter.buffer_pos]); err != nil {
+			return yaml_emitter_set_writer_error(emitter, "write error: "+err.Error())
+		}
+		emitter.buffer_pos = 0
+		return true
+	}
+
+	// Recode the buffer into the raw buffer.
+	var low, high int
+	if emitter.encoding == yaml_UTF16LE_ENCODING {
+		low, high = 0, 1
+	} else {
+		high, low = 1, 0
+	}
+
+	pos := 0
+	for pos < emitter.buffer_pos {
+		// See the "reader.c" code for more details on UTF-8 encoding.  Note
+		// that we assume that the buffer contains a valid UTF-8 sequence.
+
+		// Read the next UTF-8 character.
+		octet := emitter.buffer[pos]
+
+		var w int
+		var value rune
+		switch {
+		case octet&0x80 == 0x00:
+			w, value = 1, rune(octet&0x7F)
+		case octet&0xE0 == 0xC0:
+			w, value = 2, rune(octet&0x1F)
+		case octet&0xF0 == 0xE0:
+			w, value = 3, rune(octet&0x0F)
+		case octet&0xF8 == 0xF0:
+			w, value = 4, rune(octet&0x07)
+		}
+		for k := 1; k < w; k++ {
+			octet = emitter.buffer[pos+k]
+			value = (value << 6) + (rune(octet) & 0x3F)
+		}
+		pos += w
+
+		// Write the character.
+		if value < 0x10000 {
+			var b [2]byte
+			b[high] = byte(value >> 8)
+			b[low] = byte(value & 0xFF)
+			emitter.raw_buffer = append(emitter.raw_buffer, b[0], b[1])
+		} else {
+			// Write the character using a surrogate pair (check "reader.c").
+			var b [4]byte
+			value -= 0x10000
+			b[high] = byte(0xD8 + (value >> 18))
+			b[low] = byte((value >> 10) & 0xFF)
+			b[high+2] = byte(0xDC + ((value >> 8) & 0xFF))
+			b[low+2] = byte(value & 0xFF)
+			emitter.raw_buffer = append(emitter.raw_buffer, b[0], b[1], b[2], b[3])
+		}
+	}
+
+	// Write the raw buffer.
+	if err := emitter.write_handler(emitter, emitter.raw_buffer); err != nil {
+		return yaml_emitter_set_writer_error(emitter, "write error: "+err.Error())
+	}
+	emitter.buffer_pos = 0
+	emitter.raw_buffer = emitter.raw_buffer[:0]
+	return true
+}
diff --git a/vendor/gopkg.in/yaml.v2/yaml.go b/vendor/gopkg.in/yaml.v2/yaml.go
new file mode 100644
index 000000000..36d6b883a
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/yaml.go
@@ -0,0 +1,346 @@
+// Package yaml implements YAML support for the Go language.
+//
+// Source code and other details for the project are available at GitHub:
+//
+//   https://github.com/go-yaml/yaml
+//
+package yaml
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+)
+
+// MapSlice encodes and decodes as a YAML map.
+// The order of keys is preserved when encoding and decoding.
+type MapSlice []MapItem
+
+// MapItem is an item in a MapSlice.
+type MapItem struct {
+	Key, Value interface{}
+}
+
+// The Unmarshaler interface may be implemented by types to customize their
+// behavior when being unmarshaled from a YAML document. The UnmarshalYAML
+// method receives a function that may be called to unmarshal the original
+// YAML value into a field or variable. It is safe to call the unmarshal
+// function parameter more than once if necessary.
+type Unmarshaler interface {
+	UnmarshalYAML(unmarshal func(interface{}) error) error
+}
+
+// The Marshaler interface may be implemented by types to customize their
+// behavior when being marshaled into a YAML document. The returned value
+// is marshaled in place of the original value implementing Marshaler.
+//
+// If an error is returned by MarshalYAML, the marshaling procedure stops
+// and returns with the provided error.
+type Marshaler interface {
+	MarshalYAML() (interface{}, error)
+}
+
+// Unmarshal decodes the first document found within the in byte slice
+// and assigns decoded values into the out value.
+//
+// Maps and pointers (to a struct, string, int, etc) are accepted as out
+// values. If an internal pointer within a struct is not initialized,
+// the yaml package will initialize it if necessary for unmarshalling
+// the provided data. The out parameter must not be nil.
+//
+// The type of the decoded values should be compatible with the respective
+// values in out. If one or more values cannot be decoded due to a type
+// mismatches, decoding continues partially until the end of the YAML
+// content, and a *yaml.TypeError is returned with details for all
+// missed values.
+//
+// Struct fields are only unmarshalled if they are exported (have an
+// upper case first letter), and are unmarshalled using the field name
+// lowercased as the default key. Custom keys may be defined via the
+// "yaml" name in the field tag: the content preceding the first comma
+// is used as the key, and the following comma-separated options are
+// used to tweak the marshalling process (see Marshal).
+// Conflicting names result in a runtime error.
+//
+// For example:
+//
+//     type T struct {
+//         F int `yaml:"a,omitempty"`
+//         B int
+//     }
+//     var t T
+//     yaml.Unmarshal([]byte("a: 1\nb: 2"), &t)
+//
+// See the documentation of Marshal for the format of tags and a list of
+// supported tag options.
+//
+func Unmarshal(in []byte, out interface{}) (err error) {
+	defer handleErr(&err)
+	d := newDecoder()
+	p := newParser(in)
+	defer p.destroy()
+	node := p.parse()
+	if node != nil {
+		v := reflect.ValueOf(out)
+		if v.Kind() == reflect.Ptr && !v.IsNil() {
+			v = v.Elem()
+		}
+		d.unmarshal(node, v)
+	}
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+// Marshal serializes the value provided into a YAML document. The structure
+// of the generated document will reflect the structure of the value itself.
+// Maps and pointers (to struct, string, int, etc) are accepted as the in value.
+//
+// Struct fields are only unmarshalled if they are exported (have an upper case
+// first letter), and are unmarshalled using the field name lowercased as the
+// default key. Custom keys may be defined via the "yaml" name in the field
+// tag: the content preceding the first comma is used as the key, and the
+// following comma-separated options are used to tweak the marshalling process.
+// Conflicting names result in a runtime error.
+//
+// The field tag format accepted is:
+//
+//     `(...) yaml:"[<key>][,<flag1>[,<flag2>]]" (...)`
+//
+// The following flags are currently supported:
+//
+//     omitempty    Only include the field if it's not set to the zero
+//                  value for the type or to empty slices or maps.
+//                  Does not apply to zero valued structs.
+//
+//     flow         Marshal using a flow style (useful for structs,
+//                  sequences and maps).
+//
+//     inline       Inline the field, which must be a struct or a map,
+//                  causing all of its fields or keys to be processed as if
+//                  they were part of the outer struct. For maps, keys must
+//                  not conflict with the yaml keys of other struct fields.
+//
+// In addition, if the key is "-", the field is ignored.
+//
+// For example:
+//
+//     type T struct {
+//         F int "a,omitempty"
+//         B int
+//     }
+//     yaml.Marshal(&T{B: 2}) // Returns "b: 2\n"
+//     yaml.Marshal(&T{F: 1}} // Returns "a: 1\nb: 0\n"
+//
+func Marshal(in interface{}) (out []byte, err error) {
+	defer handleErr(&err)
+	e := newEncoder()
+	defer e.destroy()
+	e.marshal("", reflect.ValueOf(in))
+	e.finish()
+	out = e.out
+	return
+}
+
+func handleErr(err *error) {
+	if v := recover(); v != nil {
+		if e, ok := v.(yamlError); ok {
+			*err = e.err
+		} else {
+			panic(v)
+		}
+	}
+}
+
+type yamlError struct {
+	err error
+}
+
+func fail(err error) {
+	panic(yamlError{err})
+}
+
+func failf(format string, args ...interface{}) {
+	panic(yamlError{fmt.Errorf("yaml: "+format, args...)})
+}
+
+// A TypeError is returned by Unmarshal when one or more fields in
+// the YAML document cannot be properly decoded into the requested
+// types. When this error is returned, the value is still
+// unmarshaled partially.
+type TypeError struct {
+	Errors []string
+}
+
+func (e *TypeError) Error() string {
+	return fmt.Sprintf("yaml: unmarshal errors:\n  %s", strings.Join(e.Errors, "\n  "))
+}
+
+// --------------------------------------------------------------------------
+// Maintain a mapping of keys to structure field indexes
+
+// The code in this section was copied from mgo/bson.
+
+// structInfo holds details for the serialization of fields of
+// a given struct.
+type structInfo struct {
+	FieldsMap  map[string]fieldInfo
+	FieldsList []fieldInfo
+
+	// InlineMap is the number of the field in the struct that
+	// contains an ,inline map, or -1 if there's none.
+	InlineMap int
+}
+
+type fieldInfo struct {
+	Key       string
+	Num       int
+	OmitEmpty bool
+	Flow      bool
+
+	// Inline holds the field index if the field is part of an inlined struct.
+	Inline []int
+}
+
+var structMap = make(map[reflect.Type]*structInfo)
+var fieldMapMutex sync.RWMutex
+
+func getStructInfo(st reflect.Type) (*structInfo, error) {
+	fieldMapMutex.RLock()
+	sinfo, found := structMap[st]
+	fieldMapMutex.RUnlock()
+	if found {
+		return sinfo, nil
+	}
+
+	n := st.NumField()
+	fieldsMap := make(map[string]fieldInfo)
+	fieldsList := make([]fieldInfo, 0, n)
+	inlineMap := -1
+	for i := 0; i != n; i++ {
+		field := st.Field(i)
+		if field.PkgPath != "" && !field.Anonymous {
+			continue // Private field
+		}
+
+		info := fieldInfo{Num: i}
+
+		tag := field.Tag.Get("yaml")
+		if tag == "" && strings.Index(string(field.Tag), ":") < 0 {
+			tag = string(field.Tag)
+		}
+		if tag == "-" {
+			continue
+		}
+
+		inline := false
+		fields := strings.Split(tag, ",")
+		if len(fields) > 1 {
+			for _, flag := range fields[1:] {
+				switch flag {
+				case "omitempty":
+					info.OmitEmpty = true
+				case "flow":
+					info.Flow = true
+				case "inline":
+					inline = true
+				default:
+					return nil, errors.New(fmt.Sprintf("Unsupported flag %q in tag %q of type %s", flag, tag, st))
+				}
+			}
+			tag = fields[0]
+		}
+
+		if inline {
+			switch field.Type.Kind() {
+			case reflect.Map:
+				if inlineMap >= 0 {
+					return nil, errors.New("Multiple ,inline maps in struct " + st.String())
+				}
+				if field.Type.Key() != reflect.TypeOf("") {
+					return nil, errors.New("Option ,inline needs a map with string keys in struct " + st.String())
+				}
+				inlineMap = info.Num
+			case reflect.Struct:
+				sinfo, err := getStructInfo(field.Type)
+				if err != nil {
+					return nil, err
+				}
+				for _, finfo := range sinfo.FieldsList {
+					if _, found := fieldsMap[finfo.Key]; found {
+						msg := "Duplicated key '" + finfo.Key + "' in struct " + st.String()
+						return nil, errors.New(msg)
+					}
+					if finfo.Inline == nil {
+						finfo.Inline = []int{i, finfo.Num}
+					} else {
+						finfo.Inline = append([]int{i}, finfo.Inline...)
+					}
+					fieldsMap[finfo.Key] = finfo
+					fieldsList = append(fieldsList, finfo)
+				}
+			default:
+				//return nil, errors.New("Option ,inline needs a struct value or map field")
+				return nil, errors.New("Option ,inline needs a struct value field")
+			}
+			continue
+		}
+
+		if tag != "" {
+			info.Key = tag
+		} else {
+			info.Key = strings.ToLower(field.Name)
+		}
+
+		if _, found = fieldsMap[info.Key]; found {
+			msg := "Duplicated key '" + info.Key + "' in struct " + st.String()
+			return nil, errors.New(msg)
+		}
+
+		fieldsList = append(fieldsList, info)
+		fieldsMap[info.Key] = info
+	}
+
+	sinfo = &structInfo{fieldsMap, fieldsList, inlineMap}
+
+	fieldMapMutex.Lock()
+	structMap[st] = sinfo
+	fieldMapMutex.Unlock()
+	return sinfo, nil
+}
+
+func isZero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.String:
+		return len(v.String()) == 0
+	case reflect.Interface, reflect.Ptr:
+		return v.IsNil()
+	case reflect.Slice:
+		return v.Len() == 0
+	case reflect.Map:
+		return v.Len() == 0
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Struct:
+		vt := v.Type()
+		for i := v.NumField() - 1; i >= 0; i-- {
+			if vt.Field(i).PkgPath != "" {
+				continue // Private field
+			}
+			if !isZero(v.Field(i)) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}
diff --git a/vendor/gopkg.in/yaml.v2/yamlh.go b/vendor/gopkg.in/yaml.v2/yamlh.go
new file mode 100644
index 000000000..d60a6b6b0
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/yamlh.go
@@ -0,0 +1,716 @@
+package yaml
+
+import (
+	"io"
+)
+
+// The version directive data.
+type yaml_version_directive_t struct {
+	major int8 // The major version number.
+	minor int8 // The minor version number.
+}
+
+// The tag directive data.
+type yaml_tag_directive_t struct {
+	handle []byte // The tag handle.
+	prefix []byte // The tag prefix.
+}
+
+type yaml_encoding_t int
+
+// The stream encoding.
+const (
+	// Let the parser choose the encoding.
+	yaml_ANY_ENCODING yaml_encoding_t = iota
+
+	yaml_UTF8_ENCODING    // The default UTF-8 encoding.
+	yaml_UTF16LE_ENCODING // The UTF-16-LE encoding with BOM.
+	yaml_UTF16BE_ENCODING // The UTF-16-BE encoding with BOM.
+)
+
+type yaml_break_t int
+
+// Line break types.
+const (
+	// Let the parser choose the break type.
+	yaml_ANY_BREAK yaml_break_t = iota
+
+	yaml_CR_BREAK   // Use CR for line breaks (Mac style).
+	yaml_LN_BREAK   // Use LN for line breaks (Unix style).
+	yaml_CRLN_BREAK // Use CR LN for line breaks (DOS style).
+)
+
+type yaml_error_type_t int
+
+// Many bad things could happen with the parser and emitter.
+const (
+	// No error is produced.
+	yaml_NO_ERROR yaml_error_type_t = iota
+
+	yaml_MEMORY_ERROR   // Cannot allocate or reallocate a block of memory.
+	yaml_READER_ERROR   // Cannot read or decode the input stream.
+	yaml_SCANNER_ERROR  // Cannot scan the input stream.
+	yaml_PARSER_ERROR   // Cannot parse the input stream.
+	yaml_COMPOSER_ERROR // Cannot compose a YAML document.
+	yaml_WRITER_ERROR   // Cannot write to the output stream.
+	yaml_EMITTER_ERROR  // Cannot emit a YAML stream.
+)
+
+// The pointer position.
+type yaml_mark_t struct {
+	index  int // The position index.
+	line   int // The position line.
+	column int // The position column.
+}
+
+// Node Styles
+
+type yaml_style_t int8
+
+type yaml_scalar_style_t yaml_style_t
+
+// Scalar styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SCALAR_STYLE yaml_scalar_style_t = iota
+
+	yaml_PLAIN_SCALAR_STYLE         // The plain scalar style.
+	yaml_SINGLE_QUOTED_SCALAR_STYLE // The single-quoted scalar style.
+	yaml_DOUBLE_QUOTED_SCALAR_STYLE // The double-quoted scalar style.
+	yaml_LITERAL_SCALAR_STYLE       // The literal scalar style.
+	yaml_FOLDED_SCALAR_STYLE        // The folded scalar style.
+)
+
+type yaml_sequence_style_t yaml_style_t
+
+// Sequence styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SEQUENCE_STYLE yaml_sequence_style_t = iota
+
+	yaml_BLOCK_SEQUENCE_STYLE // The block sequence style.
+	yaml_FLOW_SEQUENCE_STYLE  // The flow sequence style.
+)
+
+type yaml_mapping_style_t yaml_style_t
+
+// Mapping styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_MAPPING_STYLE yaml_mapping_style_t = iota
+
+	yaml_BLOCK_MAPPING_STYLE // The block mapping style.
+	yaml_FLOW_MAPPING_STYLE  // The flow mapping style.
+)
+
+// Tokens
+
+type yaml_token_type_t int
+
+// Token types.
+const (
+	// An empty token.
+	yaml_NO_TOKEN yaml_token_type_t = iota
+
+	yaml_STREAM_START_TOKEN // A STREAM-START token.
+	yaml_STREAM_END_TOKEN   // A STREAM-END token.
+
+	yaml_VERSION_DIRECTIVE_TOKEN // A VERSION-DIRECTIVE token.
+	yaml_TAG_DIRECTIVE_TOKEN     // A TAG-DIRECTIVE token.
+	yaml_DOCUMENT_START_TOKEN    // A DOCUMENT-START token.
+	yaml_DOCUMENT_END_TOKEN      // A DOCUMENT-END token.
+
+	yaml_BLOCK_SEQUENCE_START_TOKEN // A BLOCK-SEQUENCE-START token.
+	yaml_BLOCK_MAPPING_START_TOKEN  // A BLOCK-SEQUENCE-END token.
+	yaml_BLOCK_END_TOKEN            // A BLOCK-END token.
+
+	yaml_FLOW_SEQUENCE_START_TOKEN // A FLOW-SEQUENCE-START token.
+	yaml_FLOW_SEQUENCE_END_TOKEN   // A FLOW-SEQUENCE-END token.
+	yaml_FLOW_MAPPING_START_TOKEN  // A FLOW-MAPPING-START token.
+	yaml_FLOW_MAPPING_END_TOKEN    // A FLOW-MAPPING-END token.
+
+	yaml_BLOCK_ENTRY_TOKEN // A BLOCK-ENTRY token.
+	yaml_FLOW_ENTRY_TOKEN  // A FLOW-ENTRY token.
+	yaml_KEY_TOKEN         // A KEY token.
+	yaml_VALUE_TOKEN       // A VALUE token.
+
+	yaml_ALIAS_TOKEN  // An ALIAS token.
+	yaml_ANCHOR_TOKEN // An ANCHOR token.
+	yaml_TAG_TOKEN    // A TAG token.
+	yaml_SCALAR_TOKEN // A SCALAR token.
+)
+
+func (tt yaml_token_type_t) String() string {
+	switch tt {
+	case yaml_NO_TOKEN:
+		return "yaml_NO_TOKEN"
+	case yaml_STREAM_START_TOKEN:
+		return "yaml_STREAM_START_TOKEN"
+	case yaml_STREAM_END_TOKEN:
+		return "yaml_STREAM_END_TOKEN"
+	case yaml_VERSION_DIRECTIVE_TOKEN:
+		return "yaml_VERSION_DIRECTIVE_TOKEN"
+	case yaml_TAG_DIRECTIVE_TOKEN:
+		return "yaml_TAG_DIRECTIVE_TOKEN"
+	case yaml_DOCUMENT_START_TOKEN:
+		return "yaml_DOCUMENT_START_TOKEN"
+	case yaml_DOCUMENT_END_TOKEN:
+		return "yaml_DOCUMENT_END_TOKEN"
+	case yaml_BLOCK_SEQUENCE_START_TOKEN:
+		return "yaml_BLOCK_SEQUENCE_START_TOKEN"
+	case yaml_BLOCK_MAPPING_START_TOKEN:
+		return "yaml_BLOCK_MAPPING_START_TOKEN"
+	case yaml_BLOCK_END_TOKEN:
+		return "yaml_BLOCK_END_TOKEN"
+	case yaml_FLOW_SEQUENCE_START_TOKEN:
+		return "yaml_FLOW_SEQUENCE_START_TOKEN"
+	case yaml_FLOW_SEQUENCE_END_TOKEN:
+		return "yaml_FLOW_SEQUENCE_END_TOKEN"
+	case yaml_FLOW_MAPPING_START_TOKEN:
+		return "yaml_FLOW_MAPPING_START_TOKEN"
+	case yaml_FLOW_MAPPING_END_TOKEN:
+		return "yaml_FLOW_MAPPING_END_TOKEN"
+	case yaml_BLOCK_ENTRY_TOKEN:
+		return "yaml_BLOCK_ENTRY_TOKEN"
+	case yaml_FLOW_ENTRY_TOKEN:
+		return "yaml_FLOW_ENTRY_TOKEN"
+	case yaml_KEY_TOKEN:
+		return "yaml_KEY_TOKEN"
+	case yaml_VALUE_TOKEN:
+		return "yaml_VALUE_TOKEN"
+	case yaml_ALIAS_TOKEN:
+		return "yaml_ALIAS_TOKEN"
+	case yaml_ANCHOR_TOKEN:
+		return "yaml_ANCHOR_TOKEN"
+	case yaml_TAG_TOKEN:
+		return "yaml_TAG_TOKEN"
+	case yaml_SCALAR_TOKEN:
+		return "yaml_SCALAR_TOKEN"
+	}
+	return "<unknown token>"
+}
+
+// The token structure.
+type yaml_token_t struct {
+	// The token type.
+	typ yaml_token_type_t
+
+	// The start/end of the token.
+	start_mark, end_mark yaml_mark_t
+
+	// The stream encoding (for yaml_STREAM_START_TOKEN).
+	encoding yaml_encoding_t
+
+	// The alias/anchor/scalar value or tag/tag directive handle
+	// (for yaml_ALIAS_TOKEN, yaml_ANCHOR_TOKEN, yaml_SCALAR_TOKEN, yaml_TAG_TOKEN, yaml_TAG_DIRECTIVE_TOKEN).
+	value []byte
+
+	// The tag suffix (for yaml_TAG_TOKEN).
+	suffix []byte
+
+	// The tag directive prefix (for yaml_TAG_DIRECTIVE_TOKEN).
+	prefix []byte
+
+	// The scalar style (for yaml_SCALAR_TOKEN).
+	style yaml_scalar_style_t
+
+	// The version directive major/minor (for yaml_VERSION_DIRECTIVE_TOKEN).
+	major, minor int8
+}
+
+// Events
+
+type yaml_event_type_t int8
+
+// Event types.
+const (
+	// An empty event.
+	yaml_NO_EVENT yaml_event_type_t = iota
+
+	yaml_STREAM_START_EVENT   // A STREAM-START event.
+	yaml_STREAM_END_EVENT     // A STREAM-END event.
+	yaml_DOCUMENT_START_EVENT // A DOCUMENT-START event.
+	yaml_DOCUMENT_END_EVENT   // A DOCUMENT-END event.
+	yaml_ALIAS_EVENT          // An ALIAS event.
+	yaml_SCALAR_EVENT         // A SCALAR event.
+	yaml_SEQUENCE_START_EVENT // A SEQUENCE-START event.
+	yaml_SEQUENCE_END_EVENT   // A SEQUENCE-END event.
+	yaml_MAPPING_START_EVENT  // A MAPPING-START event.
+	yaml_MAPPING_END_EVENT    // A MAPPING-END event.
+)
+
+// The event structure.
+type yaml_event_t struct {
+
+	// The event type.
+	typ yaml_event_type_t
+
+	// The start and end of the event.
+	start_mark, end_mark yaml_mark_t
+
+	// The document encoding (for yaml_STREAM_START_EVENT).
+	encoding yaml_encoding_t
+
+	// The version directive (for yaml_DOCUMENT_START_EVENT).
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives (for yaml_DOCUMENT_START_EVENT).
+	tag_directives []yaml_tag_directive_t
+
+	// The anchor (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_ALIAS_EVENT).
+	anchor []byte
+
+	// The tag (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	tag []byte
+
+	// The scalar value (for yaml_SCALAR_EVENT).
+	value []byte
+
+	// Is the document start/end indicator implicit, or the tag optional?
+	// (for yaml_DOCUMENT_START_EVENT, yaml_DOCUMENT_END_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_SCALAR_EVENT).
+	implicit bool
+
+	// Is the tag optional for any non-plain style? (for yaml_SCALAR_EVENT).
+	quoted_implicit bool
+
+	// The style (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	style yaml_style_t
+}
+
+func (e *yaml_event_t) scalar_style() yaml_scalar_style_t     { return yaml_scalar_style_t(e.style) }
+func (e *yaml_event_t) sequence_style() yaml_sequence_style_t { return yaml_sequence_style_t(e.style) }
+func (e *yaml_event_t) mapping_style() yaml_mapping_style_t   { return yaml_mapping_style_t(e.style) }
+
+// Nodes
+
+const (
+	yaml_NULL_TAG      = "tag:yaml.org,2002:null"      // The tag !!null with the only possible value: null.
+	yaml_BOOL_TAG      = "tag:yaml.org,2002:bool"      // The tag !!bool with the values: true and false.
+	yaml_STR_TAG       = "tag:yaml.org,2002:str"       // The tag !!str for string values.
+	yaml_INT_TAG       = "tag:yaml.org,2002:int"       // The tag !!int for integer values.
+	yaml_FLOAT_TAG     = "tag:yaml.org,2002:float"     // The tag !!float for float values.
+	yaml_TIMESTAMP_TAG = "tag:yaml.org,2002:timestamp" // The tag !!timestamp for date and time values.
+
+	yaml_SEQ_TAG = "tag:yaml.org,2002:seq" // The tag !!seq is used to denote sequences.
+	yaml_MAP_TAG = "tag:yaml.org,2002:map" // The tag !!map is used to denote mapping.
+
+	// Not in original libyaml.
+	yaml_BINARY_TAG = "tag:yaml.org,2002:binary"
+	yaml_MERGE_TAG  = "tag:yaml.org,2002:merge"
+
+	yaml_DEFAULT_SCALAR_TAG   = yaml_STR_TAG // The default scalar tag is !!str.
+	yaml_DEFAULT_SEQUENCE_TAG = yaml_SEQ_TAG // The default sequence tag is !!seq.
+	yaml_DEFAULT_MAPPING_TAG  = yaml_MAP_TAG // The default mapping tag is !!map.
+)
+
+type yaml_node_type_t int
+
+// Node types.
+const (
+	// An empty node.
+	yaml_NO_NODE yaml_node_type_t = iota
+
+	yaml_SCALAR_NODE   // A scalar node.
+	yaml_SEQUENCE_NODE // A sequence node.
+	yaml_MAPPING_NODE  // A mapping node.
+)
+
+// An element of a sequence node.
+type yaml_node_item_t int
+
+// An element of a mapping node.
+type yaml_node_pair_t struct {
+	key   int // The key of the element.
+	value int // The value of the element.
+}
+
+// The node structure.
+type yaml_node_t struct {
+	typ yaml_node_type_t // The node type.
+	tag []byte           // The node tag.
+
+	// The node data.
+
+	// The scalar parameters (for yaml_SCALAR_NODE).
+	scalar struct {
+		value  []byte              // The scalar value.
+		length int                 // The length of the scalar value.
+		style  yaml_scalar_style_t // The scalar style.
+	}
+
+	// The sequence parameters (for YAML_SEQUENCE_NODE).
+	sequence struct {
+		items_data []yaml_node_item_t    // The stack of sequence items.
+		style      yaml_sequence_style_t // The sequence style.
+	}
+
+	// The mapping parameters (for yaml_MAPPING_NODE).
+	mapping struct {
+		pairs_data  []yaml_node_pair_t   // The stack of mapping pairs (key, value).
+		pairs_start *yaml_node_pair_t    // The beginning of the stack.
+		pairs_end   *yaml_node_pair_t    // The end of the stack.
+		pairs_top   *yaml_node_pair_t    // The top of the stack.
+		style       yaml_mapping_style_t // The mapping style.
+	}
+
+	start_mark yaml_mark_t // The beginning of the node.
+	end_mark   yaml_mark_t // The end of the node.
+
+}
+
+// The document structure.
+type yaml_document_t struct {
+
+	// The document nodes.
+	nodes []yaml_node_t
+
+	// The version directive.
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives.
+	tag_directives_data  []yaml_tag_directive_t
+	tag_directives_start int // The beginning of the tag directives list.
+	tag_directives_end   int // The end of the tag directives list.
+
+	start_implicit int // Is the document start indicator implicit?
+	end_implicit   int // Is the document end indicator implicit?
+
+	// The start/end of the document.
+	start_mark, end_mark yaml_mark_t
+}
+
+// The prototype of a read handler.
+//
+// The read handler is called when the parser needs to read more bytes from the
+// source. The handler should write not more than size bytes to the buffer.
+// The number of written bytes should be set to the size_read variable.
+//
+// [in,out]   data        A pointer to an application data specified by
+//                        yaml_parser_set_input().
+// [out]      buffer      The buffer to write the data from the source.
+// [in]       size        The size of the buffer.
+// [out]      size_read   The actual number of bytes read from the source.
+//
+// On success, the handler should return 1.  If the handler failed,
+// the returned value should be 0. On EOF, the handler should set the
+// size_read to 0 and return 1.
+type yaml_read_handler_t func(parser *yaml_parser_t, buffer []byte) (n int, err error)
+
+// This structure holds information about a potential simple key.
+type yaml_simple_key_t struct {
+	possible     bool        // Is a simple key possible?
+	required     bool        // Is a simple key required?
+	token_number int         // The number of the token.
+	mark         yaml_mark_t // The position mark.
+}
+
+// The states of the parser.
+type yaml_parser_state_t int
+
+const (
+	yaml_PARSE_STREAM_START_STATE yaml_parser_state_t = iota
+
+	yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE           // Expect the beginning of an implicit document.
+	yaml_PARSE_DOCUMENT_START_STATE                    // Expect DOCUMENT-START.
+	yaml_PARSE_DOCUMENT_CONTENT_STATE                  // Expect the content of a document.
+	yaml_PARSE_DOCUMENT_END_STATE                      // Expect DOCUMENT-END.
+	yaml_PARSE_BLOCK_NODE_STATE                        // Expect a block node.
+	yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE // Expect a block node or indentless sequence.
+	yaml_PARSE_FLOW_NODE_STATE                         // Expect a flow node.
+	yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE        // Expect the first entry of a block sequence.
+	yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE              // Expect an entry of a block sequence.
+	yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE         // Expect an entry of an indentless sequence.
+	yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE           // Expect the first key of a block mapping.
+	yaml_PARSE_BLOCK_MAPPING_KEY_STATE                 // Expect a block mapping key.
+	yaml_PARSE_BLOCK_MAPPING_VALUE_STATE               // Expect a block mapping value.
+	yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE         // Expect the first entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE               // Expect an entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE   // Expect a key of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE // Expect a value of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE   // Expect the and of an ordered mapping entry.
+	yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE            // Expect the first key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_KEY_STATE                  // Expect a key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_VALUE_STATE                // Expect a value of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE          // Expect an empty value of a flow mapping.
+	yaml_PARSE_END_STATE                               // Expect nothing.
+)
+
+func (ps yaml_parser_state_t) String() string {
+	switch ps {
+	case yaml_PARSE_STREAM_START_STATE:
+		return "yaml_PARSE_STREAM_START_STATE"
+	case yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE:
+		return "yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_START_STATE:
+		return "yaml_PARSE_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_CONTENT_STATE:
+		return "yaml_PARSE_DOCUMENT_CONTENT_STATE"
+	case yaml_PARSE_DOCUMENT_END_STATE:
+		return "yaml_PARSE_DOCUMENT_END_STATE"
+	case yaml_PARSE_BLOCK_NODE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_STATE"
+	case yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE"
+	case yaml_PARSE_FLOW_NODE_STATE:
+		return "yaml_PARSE_FLOW_NODE_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE"
+	case yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE"
+	case yaml_PARSE_END_STATE:
+		return "yaml_PARSE_END_STATE"
+	}
+	return "<unknown parser state>"
+}
+
+// This structure holds aliases data.
+type yaml_alias_data_t struct {
+	anchor []byte      // The anchor.
+	index  int         // The node id.
+	mark   yaml_mark_t // The anchor mark.
+}
+
+// The parser structure.
+//
+// All members are internal. Manage the structure using the
+// yaml_parser_ family of functions.
+type yaml_parser_t struct {
+
+	// Error handling
+
+	error yaml_error_type_t // Error type.
+
+	problem string // Error description.
+
+	// The byte about which the problem occured.
+	problem_offset int
+	problem_value  int
+	problem_mark   yaml_mark_t
+
+	// The error context.
+	context      string
+	context_mark yaml_mark_t
+
+	// Reader stuff
+
+	read_handler yaml_read_handler_t // Read handler.
+
+	input_file io.Reader // File input data.
+	input      []byte    // String input data.
+	input_pos  int
+
+	eof bool // EOF flag
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	unread int // The number of unread characters in the buffer.
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The input encoding.
+
+	offset int         // The offset of the current position (in bytes).
+	mark   yaml_mark_t // The mark of the current position.
+
+	// Scanner stuff
+
+	stream_start_produced bool // Have we started to scan the input stream?
+	stream_end_produced   bool // Have we reached the end of the input stream?
+
+	flow_level int // The number of unclosed '[' and '{' indicators.
+
+	tokens          []yaml_token_t // The tokens queue.
+	tokens_head     int            // The head of the tokens queue.
+	tokens_parsed   int            // The number of tokens fetched from the queue.
+	token_available bool           // Does the tokens queue contain a token ready for dequeueing.
+
+	indent  int   // The current indentation level.
+	indents []int // The indentation levels stack.
+
+	simple_key_allowed bool                // May a simple key occur at the current position?
+	simple_keys        []yaml_simple_key_t // The stack of simple keys.
+
+	// Parser stuff
+
+	state          yaml_parser_state_t    // The current parser state.
+	states         []yaml_parser_state_t  // The parser states stack.
+	marks          []yaml_mark_t          // The stack of marks.
+	tag_directives []yaml_tag_directive_t // The list of TAG directives.
+
+	// Dumper stuff
+
+	aliases []yaml_alias_data_t // The alias data.
+
+	document *yaml_document_t // The currently parsed document.
+}
+
+// Emitter Definitions
+
+// The prototype of a write handler.
+//
+// The write handler is called when the emitter needs to flush the accumulated
+// characters to the output.  The handler should write @a size bytes of the
+// @a buffer to the output.
+//
+// @param[in,out]   data        A pointer to an application data specified by
+//                              yaml_emitter_set_output().
+// @param[in]       buffer      The buffer with bytes to be written.
+// @param[in]       size        The size of the buffer.
+//
+// @returns On success, the handler should return @c 1.  If the handler failed,
+// the returned value should be @c 0.
+//
+type yaml_write_handler_t func(emitter *yaml_emitter_t, buffer []byte) error
+
+type yaml_emitter_state_t int
+
+// The emitter states.
+const (
+	// Expect STREAM-START.
+	yaml_EMIT_STREAM_START_STATE yaml_emitter_state_t = iota
+
+	yaml_EMIT_FIRST_DOCUMENT_START_STATE       // Expect the first DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_START_STATE             // Expect DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_CONTENT_STATE           // Expect the content of a document.
+	yaml_EMIT_DOCUMENT_END_STATE               // Expect DOCUMENT-END.
+	yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE   // Expect the first item of a flow sequence.
+	yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE         // Expect an item of a flow sequence.
+	yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE     // Expect the first key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_KEY_STATE           // Expect a key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE  // Expect a value for a simple key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_VALUE_STATE         // Expect a value of a flow mapping.
+	yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE  // Expect the first item of a block sequence.
+	yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE        // Expect an item of a block sequence.
+	yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE    // Expect the first key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_KEY_STATE          // Expect the key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE // Expect a value for a simple key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_VALUE_STATE        // Expect a value of a block mapping.
+	yaml_EMIT_END_STATE                        // Expect nothing.
+)
+
+// The emitter structure.
+//
+// All members are internal.  Manage the structure using the @c yaml_emitter_
+// family of functions.
+type yaml_emitter_t struct {
+
+	// Error handling
+
+	error   yaml_error_type_t // Error type.
+	problem string            // Error description.
+
+	// Writer stuff
+
+	write_handler yaml_write_handler_t // Write handler.
+
+	output_buffer *[]byte   // String output data.
+	output_file   io.Writer // File output data.
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The stream encoding.
+
+	// Emitter stuff
+
+	canonical   bool         // If the output is in the canonical style?
+	best_indent int          // The number of indentation spaces.
+	best_width  int          // The preferred width of the output lines.
+	unicode     bool         // Allow unescaped non-ASCII characters?
+	line_break  yaml_break_t // The preferred line break.
+
+	state  yaml_emitter_state_t   // The current emitter state.
+	states []yaml_emitter_state_t // The stack of states.
+
+	events      []yaml_event_t // The event queue.
+	events_head int            // The head of the event queue.
+
+	indents []int // The stack of indentation levels.
+
+	tag_directives []yaml_tag_directive_t // The list of tag directives.
+
+	indent int // The current indentation level.
+
+	flow_level int // The current flow level.
+
+	root_context       bool // Is it the document root context?
+	sequence_context   bool // Is it a sequence context?
+	mapping_context    bool // Is it a mapping context?
+	simple_key_context bool // Is it a simple mapping key context?
+
+	line       int  // The current line.
+	column     int  // The current column.
+	whitespace bool // If the last character was a whitespace?
+	indention  bool // If the last character was an indentation character (' ', '-', '?', ':')?
+	open_ended bool // If an explicit document end is required?
+
+	// Anchor analysis.
+	anchor_data struct {
+		anchor []byte // The anchor value.
+		alias  bool   // Is it an alias?
+	}
+
+	// Tag analysis.
+	tag_data struct {
+		handle []byte // The tag handle.
+		suffix []byte // The tag suffix.
+	}
+
+	// Scalar analysis.
+	scalar_data struct {
+		value                 []byte              // The scalar value.
+		multiline             bool                // Does the scalar contain line breaks?
+		flow_plain_allowed    bool                // Can the scalar be expessed in the flow plain style?
+		block_plain_allowed   bool                // Can the scalar be expressed in the block plain style?
+		single_quoted_allowed bool                // Can the scalar be expressed in the single quoted style?
+		block_allowed         bool                // Can the scalar be expressed in the literal or folded styles?
+		style                 yaml_scalar_style_t // The output style.
+	}
+
+	// Dumper stuff
+
+	opened bool // If the stream was already opened?
+	closed bool // If the stream was already closed?
+
+	// The information associated with the document nodes.
+	anchors *struct {
+		references int  // The number of references.
+		anchor     int  // The anchor id.
+		serialized bool // If the node has been emitted?
+	}
+
+	last_anchor_id int // The last assigned anchor id.
+
+	document *yaml_document_t // The currently emitted document.
+}
diff --git a/vendor/gopkg.in/yaml.v2/yamlprivateh.go b/vendor/gopkg.in/yaml.v2/yamlprivateh.go
new file mode 100644
index 000000000..8110ce3c3
--- /dev/null
+++ b/vendor/gopkg.in/yaml.v2/yamlprivateh.go
@@ -0,0 +1,173 @@
+package yaml
+
+const (
+	// The size of the input raw buffer.
+	input_raw_buffer_size = 512
+
+	// The size of the input buffer.
+	// It should be possible to decode the whole raw buffer.
+	input_buffer_size = input_raw_buffer_size * 3
+
+	// The size of the output buffer.
+	output_buffer_size = 128
+
+	// The size of the output raw buffer.
+	// It should be possible to encode the whole output buffer.
+	output_raw_buffer_size = (output_buffer_size*2 + 2)
+
+	// The size of other stacks and queues.
+	initial_stack_size  = 16
+	initial_queue_size  = 16
+	initial_string_size = 16
+)
+
+// Check if the character at the specified position is an alphabetical
+// character, a digit, '_', or '-'.
+func is_alpha(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'Z' || b[i] >= 'a' && b[i] <= 'z' || b[i] == '_' || b[i] == '-'
+}
+
+// Check if the character at the specified position is a digit.
+func is_digit(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9'
+}
+
+// Get the value of a digit.
+func as_digit(b []byte, i int) int {
+	return int(b[i]) - '0'
+}
+
+// Check if the character at the specified position is a hex-digit.
+func is_hex(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'F' || b[i] >= 'a' && b[i] <= 'f'
+}
+
+// Get the value of a hex-digit.
+func as_hex(b []byte, i int) int {
+	bi := b[i]
+	if bi >= 'A' && bi <= 'F' {
+		return int(bi) - 'A' + 10
+	}
+	if bi >= 'a' && bi <= 'f' {
+		return int(bi) - 'a' + 10
+	}
+	return int(bi) - '0'
+}
+
+// Check if the character is ASCII.
+func is_ascii(b []byte, i int) bool {
+	return b[i] <= 0x7F
+}
+
+// Check if the character at the start of the buffer can be printed unescaped.
+func is_printable(b []byte, i int) bool {
+	return ((b[i] == 0x0A) || // . == #x0A
+		(b[i] >= 0x20 && b[i] <= 0x7E) || // #x20 <= . <= #x7E
+		(b[i] == 0xC2 && b[i+1] >= 0xA0) || // #0xA0 <= . <= #xD7FF
+		(b[i] > 0xC2 && b[i] < 0xED) ||
+		(b[i] == 0xED && b[i+1] < 0xA0) ||
+		(b[i] == 0xEE) ||
+		(b[i] == 0xEF && // #xE000 <= . <= #xFFFD
+			!(b[i+1] == 0xBB && b[i+2] == 0xBF) && // && . != #xFEFF
+			!(b[i+1] == 0xBF && (b[i+2] == 0xBE || b[i+2] == 0xBF))))
+}
+
+// Check if the character at the specified position is NUL.
+func is_z(b []byte, i int) bool {
+	return b[i] == 0x00
+}
+
+// Check if the beginning of the buffer is a BOM.
+func is_bom(b []byte, i int) bool {
+	return b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF
+}
+
+// Check if the character at the specified position is space.
+func is_space(b []byte, i int) bool {
+	return b[i] == ' '
+}
+
+// Check if the character at the specified position is tab.
+func is_tab(b []byte, i int) bool {
+	return b[i] == '\t'
+}
+
+// Check if the character at the specified position is blank (space or tab).
+func is_blank(b []byte, i int) bool {
+	//return is_space(b, i) || is_tab(b, i)
+	return b[i] == ' ' || b[i] == '\t'
+}
+
+// Check if the character at the specified position is a line break.
+func is_break(b []byte, i int) bool {
+	return (b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9) // PS (#x2029)
+}
+
+func is_crlf(b []byte, i int) bool {
+	return b[i] == '\r' && b[i+1] == '\n'
+}
+
+// Check if the character is a line break or NUL.
+func is_breakz(b []byte, i int) bool {
+	//return is_break(b, i) || is_z(b, i)
+	return (        // is_break:
+	b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		// is_z:
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, or NUL.
+func is_spacez(b []byte, i int) bool {
+	//return is_space(b, i) || is_breakz(b, i)
+	return ( // is_space:
+	b[i] == ' ' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, tab, or NUL.
+func is_blankz(b []byte, i int) bool {
+	//return is_blank(b, i) || is_breakz(b, i)
+	return ( // is_blank:
+	b[i] == ' ' || b[i] == '\t' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Determine the width of the character.
+func width(b byte) int {
+	// Don't replace these by a switch without first
+	// confirming that it is being inlined.
+	if b&0x80 == 0x00 {
+		return 1
+	}
+	if b&0xE0 == 0xC0 {
+		return 2
+	}
+	if b&0xF0 == 0xE0 {
+		return 3
+	}
+	if b&0xF8 == 0xF0 {
+		return 4
+	}
+	return 0
+
+}