diff --git a/vendor/golang.org/x/text/unicode/cldr/collate.go b/vendor/golang.org/x/text/unicode/cldr/collate.go
new file mode 100644
index 0000000..27c5bac
--- /dev/null
+++ b/vendor/golang.org/x/text/unicode/cldr/collate.go
@@ -0,0 +1,359 @@
+// 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.
+
+package cldr
+
+import (
+	"bufio"
+	"encoding/xml"
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// RuleProcessor can be passed to Collator's Process method, which
+// parses the rules and calls the respective method for each rule found.
+type RuleProcessor interface {
+	Reset(anchor string, before int) error
+	Insert(level int, str, context, extend string) error
+	Index(id string)
+}
+
+const (
+	// cldrIndex is a Unicode-reserved sentinel value used to mark the start
+	// of a grouping within an index.
+	// We ignore any rule that starts with this rune.
+	// See https://unicode.org/reports/tr35/#Collation_Elements for details.
+	cldrIndex = "\uFDD0"
+
+	// specialAnchor is the format in which to represent logical reset positions,
+	// such as "first tertiary ignorable".
+	specialAnchor = "<%s/>"
+)
+
+// Process parses the rules for the tailorings of this collation
+// and calls the respective methods of p for each rule found.
+func (c Collation) Process(p RuleProcessor) (err error) {
+	if len(c.Cr) > 0 {
+		if len(c.Cr) > 1 {
+			return fmt.Errorf("multiple cr elements, want 0 or 1")
+		}
+		return processRules(p, c.Cr[0].Data())
+	}
+	if c.Rules.Any != nil {
+		return c.processXML(p)
+	}
+	return errors.New("no tailoring data")
+}
+
+// processRules parses rules in the Collation Rule Syntax defined in
+// https://www.unicode.org/reports/tr35/tr35-collation.html#Collation_Tailorings.
+func processRules(p RuleProcessor, s string) (err error) {
+	chk := func(s string, e error) string {
+		if err == nil {
+			err = e
+		}
+		return s
+	}
+	i := 0 // Save the line number for use after the loop.
+	scanner := bufio.NewScanner(strings.NewReader(s))
+	for ; scanner.Scan() && err == nil; i++ {
+		for s := skipSpace(scanner.Text()); s != "" && s[0] != '#'; s = skipSpace(s) {
+			level := 5
+			var ch byte
+			switch ch, s = s[0], s[1:]; ch {
+			case '&': // followed by <anchor> or '[' <key> ']'
+				if s = skipSpace(s); consume(&s, '[') {
+					s = chk(parseSpecialAnchor(p, s))
+				} else {
+					s = chk(parseAnchor(p, 0, s))
+				}
+			case '<': // sort relation '<'{1,4}, optionally followed by '*'.
+				for level = 1; consume(&s, '<'); level++ {
+				}
+				if level > 4 {
+					err = fmt.Errorf("level %d > 4", level)
+				}
+				fallthrough
+			case '=': // identity relation, optionally followed by *.
+				if consume(&s, '*') {
+					s = chk(parseSequence(p, level, s))
+				} else {
+					s = chk(parseOrder(p, level, s))
+				}
+			default:
+				chk("", fmt.Errorf("illegal operator %q", ch))
+				break
+			}
+		}
+	}
+	if chk("", scanner.Err()); err != nil {
+		return fmt.Errorf("%d: %v", i, err)
+	}
+	return nil
+}
+
+// parseSpecialAnchor parses the anchor syntax which is either of the form
+//    ['before' <level>] <anchor>
+// or
+//    [<label>]
+// The starting should already be consumed.
+func parseSpecialAnchor(p RuleProcessor, s string) (tail string, err error) {
+	i := strings.IndexByte(s, ']')
+	if i == -1 {
+		return "", errors.New("unmatched bracket")
+	}
+	a := strings.TrimSpace(s[:i])
+	s = s[i+1:]
+	if strings.HasPrefix(a, "before ") {
+		l, err := strconv.ParseUint(skipSpace(a[len("before "):]), 10, 3)
+		if err != nil {
+			return s, err
+		}
+		return parseAnchor(p, int(l), s)
+	}
+	return s, p.Reset(fmt.Sprintf(specialAnchor, a), 0)
+}
+
+func parseAnchor(p RuleProcessor, level int, s string) (tail string, err error) {
+	anchor, s, err := scanString(s)
+	if err != nil {
+		return s, err
+	}
+	return s, p.Reset(anchor, level)
+}
+
+func parseOrder(p RuleProcessor, level int, s string) (tail string, err error) {
+	var value, context, extend string
+	if value, s, err = scanString(s); err != nil {
+		return s, err
+	}
+	if strings.HasPrefix(value, cldrIndex) {
+		p.Index(value[len(cldrIndex):])
+		return
+	}
+	if consume(&s, '|') {
+		if context, s, err = scanString(s); err != nil {
+			return s, errors.New("missing string after context")
+		}
+	}
+	if consume(&s, '/') {
+		if extend, s, err = scanString(s); err != nil {
+			return s, errors.New("missing string after extension")
+		}
+	}
+	return s, p.Insert(level, value, context, extend)
+}
+
+// scanString scans a single input string.
+func scanString(s string) (str, tail string, err error) {
+	if s = skipSpace(s); s == "" {
+		return s, s, errors.New("missing string")
+	}
+	buf := [16]byte{} // small but enough to hold most cases.
+	value := buf[:0]
+	for s != "" {
+		if consume(&s, '\'') {
+			i := strings.IndexByte(s, '\'')
+			if i == -1 {
+				return "", "", errors.New(`unmatched single quote`)
+			}
+			if i == 0 {
+				value = append(value, '\'')
+			} else {
+				value = append(value, s[:i]...)
+			}
+			s = s[i+1:]
+			continue
+		}
+		r, sz := utf8.DecodeRuneInString(s)
+		if unicode.IsSpace(r) || strings.ContainsRune("&<=#", r) {
+			break
+		}
+		value = append(value, s[:sz]...)
+		s = s[sz:]
+	}
+	return string(value), skipSpace(s), nil
+}
+
+func parseSequence(p RuleProcessor, level int, s string) (tail string, err error) {
+	if s = skipSpace(s); s == "" {
+		return s, errors.New("empty sequence")
+	}
+	last := rune(0)
+	for s != "" {
+		r, sz := utf8.DecodeRuneInString(s)
+		s = s[sz:]
+
+		if r == '-' {
+			// We have a range. The first element was already written.
+			if last == 0 {
+				return s, errors.New("range without starter value")
+			}
+			r, sz = utf8.DecodeRuneInString(s)
+			s = s[sz:]
+			if r == utf8.RuneError || r < last {
+				return s, fmt.Errorf("invalid range %q-%q", last, r)
+			}
+			for i := last + 1; i <= r; i++ {
+				if err := p.Insert(level, string(i), "", ""); err != nil {
+					return s, err
+				}
+			}
+			last = 0
+			continue
+		}
+
+		if unicode.IsSpace(r) || unicode.IsPunct(r) {
+			break
+		}
+
+		// normal case
+		if err := p.Insert(level, string(r), "", ""); err != nil {
+			return s, err
+		}
+		last = r
+	}
+	return s, nil
+}
+
+func skipSpace(s string) string {
+	return strings.TrimLeftFunc(s, unicode.IsSpace)
+}
+
+// consumes returns whether the next byte is ch. If so, it gobbles it by
+// updating s.
+func consume(s *string, ch byte) (ok bool) {
+	if *s == "" || (*s)[0] != ch {
+		return false
+	}
+	*s = (*s)[1:]
+	return true
+}
+
+// The following code parses Collation rules of CLDR version 24 and before.
+
+var lmap = map[byte]int{
+	'p': 1,
+	's': 2,
+	't': 3,
+	'i': 5,
+}
+
+type rulesElem struct {
+	Rules struct {
+		Common
+		Any []*struct {
+			XMLName xml.Name
+			rule
+		} `xml:",any"`
+	} `xml:"rules"`
+}
+
+type rule struct {
+	Value  string `xml:",chardata"`
+	Before string `xml:"before,attr"`
+	Any    []*struct {
+		XMLName xml.Name
+		rule
+	} `xml:",any"`
+}
+
+var emptyValueError = errors.New("cldr: empty rule value")
+
+func (r *rule) value() (string, error) {
+	// Convert hexadecimal Unicode codepoint notation to a string.
+	s := charRe.ReplaceAllStringFunc(r.Value, replaceUnicode)
+	r.Value = s
+	if s == "" {
+		if len(r.Any) != 1 {
+			return "", emptyValueError
+		}
+		r.Value = fmt.Sprintf(specialAnchor, r.Any[0].XMLName.Local)
+		r.Any = nil
+	} else if len(r.Any) != 0 {
+		return "", fmt.Errorf("cldr: XML elements found in collation rule: %v", r.Any)
+	}
+	return r.Value, nil
+}
+
+func (r rule) process(p RuleProcessor, name, context, extend string) error {
+	v, err := r.value()
+	if err != nil {
+		return err
+	}
+	switch name {
+	case "p", "s", "t", "i":
+		if strings.HasPrefix(v, cldrIndex) {
+			p.Index(v[len(cldrIndex):])
+			return nil
+		}
+		if err := p.Insert(lmap[name[0]], v, context, extend); err != nil {
+			return err
+		}
+	case "pc", "sc", "tc", "ic":
+		level := lmap[name[0]]
+		for _, s := range v {
+			if err := p.Insert(level, string(s), context, extend); err != nil {
+				return err
+			}
+		}
+	default:
+		return fmt.Errorf("cldr: unsupported tag: %q", name)
+	}
+	return nil
+}
+
+// processXML parses the format of CLDR versions 24 and older.
+func (c Collation) processXML(p RuleProcessor) (err error) {
+	// Collation is generated and defined in xml.go.
+	var v string
+	for _, r := range c.Rules.Any {
+		switch r.XMLName.Local {
+		case "reset":
+			level := 0
+			switch r.Before {
+			case "primary", "1":
+				level = 1
+			case "secondary", "2":
+				level = 2
+			case "tertiary", "3":
+				level = 3
+			case "":
+			default:
+				return fmt.Errorf("cldr: unknown level %q", r.Before)
+			}
+			v, err = r.value()
+			if err == nil {
+				err = p.Reset(v, level)
+			}
+		case "x":
+			var context, extend string
+			for _, r1 := range r.Any {
+				v, err = r1.value()
+				switch r1.XMLName.Local {
+				case "context":
+					context = v
+				case "extend":
+					extend = v
+				}
+			}
+			for _, r1 := range r.Any {
+				if t := r1.XMLName.Local; t == "context" || t == "extend" {
+					continue
+				}
+				r1.rule.process(p, r1.XMLName.Local, context, extend)
+			}
+		default:
+			err = r.rule.process(p, r.XMLName.Local, "", "")
+		}
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}