vendor: update all dependencies

* Update all dependencies
  * Remove all `[[constraint]]` from Gopkg.toml
  * Add in the minimum number of `[[override]]` to build
  * Remove go get of github.com/inconshreveable/mousetrap as it is vendored
  * Update docs with new policy on constraints

vendor/github.com/golang/protobuf/proto/text_parser.go

@@ -206,7 +206,6 @@ func (p *textParser) advance() {
 
 var (
 	errBadUTF8 = errors.New("proto: bad UTF-8")
-	errBadHex  = errors.New("proto: bad hexadecimal")
 )
 
 func unquoteC(s string, quote rune) (string, error) {
@@ -277,60 +276,47 @@ func unescape(s string) (ch string, tail string, err error) {
 		return "?", s, nil // trigraph workaround
 	case '\'', '"', '\\':
 		return string(r), s, nil
-	case '0', '1', '2', '3', '4', '5', '6', '7', 'x', 'X':
+	case '0', '1', '2', '3', '4', '5', '6', '7':
 		if len(s) < 2 {
 			return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
 		}
-		base := 8
-		ss := s[:2]
+		ss := string(r) + s[:2]
 		s = s[2:]
-		if r == 'x' || r == 'X' {
-			base = 16
-		} else {
-			ss = string(r) + ss
-		}
-		i, err := strconv.ParseUint(ss, base, 8)
+		i, err := strconv.ParseUint(ss, 8, 8)
 		if err != nil {
-			return "", "", err
+			return "", "", fmt.Errorf(`\%s contains non-octal digits`, ss)
 		}
 		return string([]byte{byte(i)}), s, nil
-	case 'u', 'U':
-		n := 4
-		if r == 'U' {
+	case 'x', 'X', 'u', 'U':
+		var n int
+		switch r {
+		case 'x', 'X':
+			n = 2
+		case 'u':
+			n = 4
+		case 'U':
 			n = 8
 		}
 		if len(s) < n {
-			return "", "", fmt.Errorf(`\%c requires %d digits`, r, n)
-		}
-
-		bs := make([]byte, n/2)
-		for i := 0; i < n; i += 2 {
-			a, ok1 := unhex(s[i])
-			b, ok2 := unhex(s[i+1])
-			if !ok1 || !ok2 {
-				return "", "", errBadHex
-			}
-			bs[i/2] = a<<4 | b
+			return "", "", fmt.Errorf(`\%c requires %d following digits`, r, n)
 		}
+		ss := s[:n]
 		s = s[n:]
-		return string(bs), s, nil
+		i, err := strconv.ParseUint(ss, 16, 64)
+		if err != nil {
+			return "", "", fmt.Errorf(`\%c%s contains non-hexadecimal digits`, r, ss)
+		}
+		if r == 'x' || r == 'X' {
+			return string([]byte{byte(i)}), s, nil
+		}
+		if i > utf8.MaxRune {
+			return "", "", fmt.Errorf(`\%c%s is not a valid Unicode code point`, r, ss)
+		}
+		return string(i), s, nil
 	}
 	return "", "", fmt.Errorf(`unknown escape \%c`, r)
 }
 
-// Adapted from src/pkg/strconv/quote.go.
-func unhex(b byte) (v byte, ok bool) {
-	switch {
-	case '0' <= b && b <= '9':
-		return b - '0', true
-	case 'a' <= b && b <= 'f':
-		return b - 'a' + 10, true
-	case 'A' <= b && b <= 'F':
-		return b - 'A' + 10, true
-	}
-	return 0, false
-}
-
 // Back off the parser by one token. Can only be done between calls to next().
 // It makes the next advance() a no-op.
 func (p *textParser) back() { p.backed = true }
@@ -728,6 +714,9 @@ func (p *textParser) consumeExtName() (string, error) {
 		if tok.err != nil {
 			return "", p.errorf("unrecognized type_url or extension name: %s", tok.err)
 		}
+		if p.done && tok.value != "]" {
+			return "", p.errorf("unclosed type_url or extension name")
+		}
 	}
 	return strings.Join(parts, ""), nil
 }
@@ -865,7 +854,7 @@ func (p *textParser) readAny(v reflect.Value, props *Properties) error {
 		return p.readStruct(fv, terminator)
 	case reflect.Uint32:
 		if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
-			fv.SetUint(x)
+			fv.SetUint(uint64(x))
 			return nil
 		}
 	case reflect.Uint64:
@@ -883,13 +872,9 @@ func (p *textParser) readAny(v reflect.Value, props *Properties) error {
 // UnmarshalText returns *RequiredNotSetError.
 func UnmarshalText(s string, pb Message) error {
 	if um, ok := pb.(encoding.TextUnmarshaler); ok {
-		err := um.UnmarshalText([]byte(s))
-		return err
+		return um.UnmarshalText([]byte(s))
 	}
 	pb.Reset()
 	v := reflect.ValueOf(pb)
-	if pe := newTextParser(s).readStruct(v.Elem(), ""); pe != nil {
-		return pe
-	}
-	return nil
+	return newTextParser(s).readStruct(v.Elem(), "")
 }