diff --git a/vendor/golang.org/x/text/internal/triegen/triegen.go b/vendor/golang.org/x/text/internal/triegen/triegen.go
new file mode 100644
index 0000000..51d218a
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+++ b/vendor/golang.org/x/text/internal/triegen/triegen.go
@@ -0,0 +1,494 @@
+// Copyright 2014 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.
+
+// Package triegen implements a code generator for a trie for associating
+// unsigned integer values with UTF-8 encoded runes.
+//
+// Many of the go.text packages use tries for storing per-rune information.  A
+// trie is especially useful if many of the runes have the same value. If this
+// is the case, many blocks can be expected to be shared allowing for
+// information on many runes to be stored in little space.
+//
+// As most of the lookups are done directly on []byte slices, the tries use the
+// UTF-8 bytes directly for the lookup. This saves a conversion from UTF-8 to
+// runes and contributes a little bit to better performance. It also naturally
+// provides a fast path for ASCII.
+//
+// Space is also an issue. There are many code points defined in Unicode and as
+// a result tables can get quite large. So every byte counts. The triegen
+// package automatically chooses the smallest integer values to represent the
+// tables. Compacters allow further compression of the trie by allowing for
+// alternative representations of individual trie blocks.
+//
+// triegen allows generating multiple tries as a single structure. This is
+// useful when, for example, one wants to generate tries for several languages
+// that have a lot of values in common. Some existing libraries for
+// internationalization store all per-language data as a dynamically loadable
+// chunk. The go.text packages are designed with the assumption that the user
+// typically wants to compile in support for all supported languages, in line
+// with the approach common to Go to create a single standalone binary. The
+// multi-root trie approach can give significant storage savings in this
+// scenario.
+//
+// triegen generates both tables and code. The code is optimized to use the
+// automatically chosen data types. The following code is generated for a Trie
+// or multiple Tries named "foo":
+//	- type fooTrie
+//		The trie type.
+//
+//	- func newFooTrie(x int) *fooTrie
+//		Trie constructor, where x is the index of the trie passed to Gen.
+//
+//	- func (t *fooTrie) lookup(s []byte) (v uintX, sz int)
+//		The lookup method, where uintX is automatically chosen.
+//
+//	- func lookupString, lookupUnsafe and lookupStringUnsafe
+//		Variants of the above.
+//
+//	- var fooValues and fooIndex and any tables generated by Compacters.
+//		The core trie data.
+//
+//	- var fooTrieHandles
+//		Indexes of starter blocks in case of multiple trie roots.
+//
+// It is recommended that users test the generated trie by checking the returned
+// value for every rune. Such exhaustive tests are possible as the number of
+// runes in Unicode is limited.
+package triegen // import "golang.org/x/text/internal/triegen"
+
+// TODO: Arguably, the internally optimized data types would not have to be
+// exposed in the generated API. We could also investigate not generating the
+// code, but using it through a package. We would have to investigate the impact
+// on performance of making such change, though. For packages like unicode/norm,
+// small changes like this could tank performance.
+
+import (
+	"encoding/binary"
+	"fmt"
+	"hash/crc64"
+	"io"
+	"log"
+	"unicode/utf8"
+)
+
+// builder builds a set of tries for associating values with runes. The set of
+// tries can share common index and value blocks.
+type builder struct {
+	Name string
+
+	// ValueType is the type of the trie values looked up.
+	ValueType string
+
+	// ValueSize is the byte size of the ValueType.
+	ValueSize int
+
+	// IndexType is the type of trie index values used for all UTF-8 bytes of
+	// a rune except the last one.
+	IndexType string
+
+	// IndexSize is the byte size of the IndexType.
+	IndexSize int
+
+	// SourceType is used when generating the lookup functions. If the user
+	// requests StringSupport, all lookup functions will be generated for
+	// string input as well.
+	SourceType string
+
+	Trie []*Trie
+
+	IndexBlocks []*node
+	ValueBlocks [][]uint64
+	Compactions []compaction
+	Checksum    uint64
+
+	ASCIIBlock   string
+	StarterBlock string
+
+	indexBlockIdx map[uint64]int
+	valueBlockIdx map[uint64]nodeIndex
+	asciiBlockIdx map[uint64]int
+
+	// Stats are used to fill out the template.
+	Stats struct {
+		NValueEntries int
+		NValueBytes   int
+		NIndexEntries int
+		NIndexBytes   int
+		NHandleBytes  int
+	}
+
+	err error
+}
+
+// A nodeIndex encodes the index of a node, which is defined by the compaction
+// which stores it and an index within the compaction. For internal nodes, the
+// compaction is always 0.
+type nodeIndex struct {
+	compaction int
+	index      int
+}
+
+// compaction keeps track of stats used for the compaction.
+type compaction struct {
+	c         Compacter
+	blocks    []*node
+	maxHandle uint32
+	totalSize int
+
+	// Used by template-based generator and thus exported.
+	Cutoff  uint32
+	Offset  uint32
+	Handler string
+}
+
+func (b *builder) setError(err error) {
+	if b.err == nil {
+		b.err = err
+	}
+}
+
+// An Option can be passed to Gen.
+type Option func(b *builder) error
+
+// Compact configures the trie generator to use the given Compacter.
+func Compact(c Compacter) Option {
+	return func(b *builder) error {
+		b.Compactions = append(b.Compactions, compaction{
+			c:       c,
+			Handler: c.Handler() + "(n, b)"})
+		return nil
+	}
+}
+
+// Gen writes Go code for a shared trie lookup structure to w for the given
+// Tries. The generated trie type will be called nameTrie. newNameTrie(x) will
+// return the *nameTrie for tries[x]. A value can be looked up by using one of
+// the various lookup methods defined on nameTrie. It returns the table size of
+// the generated trie.
+func Gen(w io.Writer, name string, tries []*Trie, opts ...Option) (sz int, err error) {
+	// The index contains two dummy blocks, followed by the zero block. The zero
+	// block is at offset 0x80, so that the offset for the zero block for
+	// continuation bytes is 0.
+	b := &builder{
+		Name:        name,
+		Trie:        tries,
+		IndexBlocks: []*node{{}, {}, {}},
+		Compactions: []compaction{{
+			Handler: name + "Values[n<<6+uint32(b)]",
+		}},
+		// The 0 key in indexBlockIdx and valueBlockIdx is the hash of the zero
+		// block.
+		indexBlockIdx: map[uint64]int{0: 0},
+		valueBlockIdx: map[uint64]nodeIndex{0: {}},
+		asciiBlockIdx: map[uint64]int{},
+	}
+	b.Compactions[0].c = (*simpleCompacter)(b)
+
+	for _, f := range opts {
+		if err := f(b); err != nil {
+			return 0, err
+		}
+	}
+	b.build()
+	if b.err != nil {
+		return 0, b.err
+	}
+	if err = b.print(w); err != nil {
+		return 0, err
+	}
+	return b.Size(), nil
+}
+
+// A Trie represents a single root node of a trie. A builder may build several
+// overlapping tries at once.
+type Trie struct {
+	root *node
+
+	hiddenTrie
+}
+
+// hiddenTrie contains values we want to be visible to the template generator,
+// but hidden from the API documentation.
+type hiddenTrie struct {
+	Name         string
+	Checksum     uint64
+	ASCIIIndex   int
+	StarterIndex int
+}
+
+// NewTrie returns a new trie root.
+func NewTrie(name string) *Trie {
+	return &Trie{
+		&node{
+			children: make([]*node, blockSize),
+			values:   make([]uint64, utf8.RuneSelf),
+		},
+		hiddenTrie{Name: name},
+	}
+}
+
+// Gen is a convenience wrapper around the Gen func passing t as the only trie
+// and uses the name passed to NewTrie. It returns the size of the generated
+// tables.
+func (t *Trie) Gen(w io.Writer, opts ...Option) (sz int, err error) {
+	return Gen(w, t.Name, []*Trie{t}, opts...)
+}
+
+// node is a node of the intermediate trie structure.
+type node struct {
+	// children holds this node's children. It is always of length 64.
+	// A child node may be nil.
+	children []*node
+
+	// values contains the values of this node. If it is non-nil, this node is
+	// either a root or leaf node:
+	// For root nodes, len(values) == 128 and it maps the bytes in [0x00, 0x7F].
+	// For leaf nodes, len(values) ==  64 and it maps the bytes in [0x80, 0xBF].
+	values []uint64
+
+	index nodeIndex
+}
+
+// Insert associates value with the given rune. Insert will panic if a non-zero
+// value is passed for an invalid rune.
+func (t *Trie) Insert(r rune, value uint64) {
+	if value == 0 {
+		return
+	}
+	s := string(r)
+	if []rune(s)[0] != r && value != 0 {
+		// Note: The UCD tables will always assign what amounts to a zero value
+		// to a surrogate. Allowing a zero value for an illegal rune allows
+		// users to iterate over [0..MaxRune] without having to explicitly
+		// exclude surrogates, which would be tedious.
+		panic(fmt.Sprintf("triegen: non-zero value for invalid rune %U", r))
+	}
+	if len(s) == 1 {
+		// It is a root node value (ASCII).
+		t.root.values[s[0]] = value
+		return
+	}
+
+	n := t.root
+	for ; len(s) > 1; s = s[1:] {
+		if n.children == nil {
+			n.children = make([]*node, blockSize)
+		}
+		p := s[0] % blockSize
+		c := n.children[p]
+		if c == nil {
+			c = &node{}
+			n.children[p] = c
+		}
+		if len(s) > 2 && c.values != nil {
+			log.Fatalf("triegen: insert(%U): found internal node with values", r)
+		}
+		n = c
+	}
+	if n.values == nil {
+		n.values = make([]uint64, blockSize)
+	}
+	if n.children != nil {
+		log.Fatalf("triegen: insert(%U): found leaf node that also has child nodes", r)
+	}
+	n.values[s[0]-0x80] = value
+}
+
+// Size returns the number of bytes the generated trie will take to store. It
+// needs to be exported as it is used in the templates.
+func (b *builder) Size() int {
+	// Index blocks.
+	sz := len(b.IndexBlocks) * blockSize * b.IndexSize
+
+	// Skip the first compaction, which represents the normal value blocks, as
+	// its totalSize does not account for the ASCII blocks, which are managed
+	// separately.
+	sz += len(b.ValueBlocks) * blockSize * b.ValueSize
+	for _, c := range b.Compactions[1:] {
+		sz += c.totalSize
+	}
+
+	// TODO: this computation does not account for the fixed overhead of a using
+	// a compaction, either code or data. As for data, though, the typical
+	// overhead of data is in the order of bytes (2 bytes for cases). Further,
+	// the savings of using a compaction should anyway be substantial for it to
+	// be worth it.
+
+	// For multi-root tries, we also need to account for the handles.
+	if len(b.Trie) > 1 {
+		sz += 2 * b.IndexSize * len(b.Trie)
+	}
+	return sz
+}
+
+func (b *builder) build() {
+	// Compute the sizes of the values.
+	var vmax uint64
+	for _, t := range b.Trie {
+		vmax = maxValue(t.root, vmax)
+	}
+	b.ValueType, b.ValueSize = getIntType(vmax)
+
+	// Compute all block allocations.
+	// TODO: first compute the ASCII blocks for all tries and then the other
+	// nodes. ASCII blocks are more restricted in placement, as they require two
+	// blocks to be placed consecutively. Processing them first may improve
+	// sharing (at least one zero block can be expected to be saved.)
+	for _, t := range b.Trie {
+		b.Checksum += b.buildTrie(t)
+	}
+
+	// Compute the offsets for all the Compacters.
+	offset := uint32(0)
+	for i := range b.Compactions {
+		c := &b.Compactions[i]
+		c.Offset = offset
+		offset += c.maxHandle + 1
+		c.Cutoff = offset
+	}
+
+	// Compute the sizes of indexes.
+	// TODO: different byte positions could have different sizes. So far we have
+	// not found a case where this is beneficial.
+	imax := uint64(b.Compactions[len(b.Compactions)-1].Cutoff)
+	for _, ib := range b.IndexBlocks {
+		if x := uint64(ib.index.index); x > imax {
+			imax = x
+		}
+	}
+	b.IndexType, b.IndexSize = getIntType(imax)
+}
+
+func maxValue(n *node, max uint64) uint64 {
+	if n == nil {
+		return max
+	}
+	for _, c := range n.children {
+		max = maxValue(c, max)
+	}
+	for _, v := range n.values {
+		if max < v {
+			max = v
+		}
+	}
+	return max
+}
+
+func getIntType(v uint64) (string, int) {
+	switch {
+	case v < 1<<8:
+		return "uint8", 1
+	case v < 1<<16:
+		return "uint16", 2
+	case v < 1<<32:
+		return "uint32", 4
+	}
+	return "uint64", 8
+}
+
+const (
+	blockSize = 64
+
+	// Subtract two blocks to offset 0x80, the first continuation byte.
+	blockOffset = 2
+
+	// Subtract three blocks to offset 0xC0, the first non-ASCII starter.
+	rootBlockOffset = 3
+)
+
+var crcTable = crc64.MakeTable(crc64.ISO)
+
+func (b *builder) buildTrie(t *Trie) uint64 {
+	n := t.root
+
+	// Get the ASCII offset. For the first trie, the ASCII block will be at
+	// position 0.
+	hasher := crc64.New(crcTable)
+	binary.Write(hasher, binary.BigEndian, n.values)
+	hash := hasher.Sum64()
+
+	v, ok := b.asciiBlockIdx[hash]
+	if !ok {
+		v = len(b.ValueBlocks)
+		b.asciiBlockIdx[hash] = v
+
+		b.ValueBlocks = append(b.ValueBlocks, n.values[:blockSize], n.values[blockSize:])
+		if v == 0 {
+			// Add the zero block at position 2 so that it will be assigned a
+			// zero reference in the lookup blocks.
+			// TODO: always do this? This would allow us to remove a check from
+			// the trie lookup, but at the expense of extra space. Analyze
+			// performance for unicode/norm.
+			b.ValueBlocks = append(b.ValueBlocks, make([]uint64, blockSize))
+		}
+	}
+	t.ASCIIIndex = v
+
+	// Compute remaining offsets.
+	t.Checksum = b.computeOffsets(n, true)
+	// We already subtracted the normal blockOffset from the index. Subtract the
+	// difference for starter bytes.
+	t.StarterIndex = n.index.index - (rootBlockOffset - blockOffset)
+	return t.Checksum
+}
+
+func (b *builder) computeOffsets(n *node, root bool) uint64 {
+	// For the first trie, the root lookup block will be at position 3, which is
+	// the offset for UTF-8 non-ASCII starter bytes.
+	first := len(b.IndexBlocks) == rootBlockOffset
+	if first {
+		b.IndexBlocks = append(b.IndexBlocks, n)
+	}
+
+	// We special-case the cases where all values recursively are 0. This allows
+	// for the use of a zero block to which all such values can be directed.
+	hash := uint64(0)
+	if n.children != nil || n.values != nil {
+		hasher := crc64.New(crcTable)
+		for _, c := range n.children {
+			var v uint64
+			if c != nil {
+				v = b.computeOffsets(c, false)
+			}
+			binary.Write(hasher, binary.BigEndian, v)
+		}
+		binary.Write(hasher, binary.BigEndian, n.values)
+		hash = hasher.Sum64()
+	}
+
+	if first {
+		b.indexBlockIdx[hash] = rootBlockOffset - blockOffset
+	}
+
+	// Compacters don't apply to internal nodes.
+	if n.children != nil {
+		v, ok := b.indexBlockIdx[hash]
+		if !ok {
+			v = len(b.IndexBlocks) - blockOffset
+			b.IndexBlocks = append(b.IndexBlocks, n)
+			b.indexBlockIdx[hash] = v
+		}
+		n.index = nodeIndex{0, v}
+	} else {
+		h, ok := b.valueBlockIdx[hash]
+		if !ok {
+			bestI, bestSize := 0, blockSize*b.ValueSize
+			for i, c := range b.Compactions[1:] {
+				if sz, ok := c.c.Size(n.values); ok && bestSize > sz {
+					bestI, bestSize = i+1, sz
+				}
+			}
+			c := &b.Compactions[bestI]
+			c.totalSize += bestSize
+			v := c.c.Store(n.values)
+			if c.maxHandle < v {
+				c.maxHandle = v
+			}
+			h = nodeIndex{bestI, int(v)}
+			b.valueBlockIdx[hash] = h
+		}
+		n.index = h
+	}
+	return hash
+}