vendor: update all dependencies to latest versions

vendor/github.com/golang/protobuf/README.md

@@ -1,6 +1,7 @@
 # Go support for Protocol Buffers
 
 [![Build Status](https://travis-ci.org/golang/protobuf.svg?branch=master)](https://travis-ci.org/golang/protobuf)
+[![GoDoc](https://godoc.org/github.com/golang/protobuf?status.svg)](https://godoc.org/github.com/golang/protobuf)
 
 Google's data interchange format.
 Copyright 2010 The Go Authors.

vendor/github.com/golang/protobuf/jsonpb/jsonpb.go

@@ -193,8 +193,7 @@ func (m *Marshaler) marshalObject(out *errWriter, v proto.Message, indent, typeU
 			// "Generated output always contains 3, 6, or 9 fractional digits,
 			//  depending on required precision."
 			s, ns := s.Field(0).Int(), s.Field(1).Int()
-			d := time.Duration(s)*time.Second + time.Duration(ns)*time.Nanosecond
-			x := fmt.Sprintf("%.9f", d.Seconds())
+			x := fmt.Sprintf("%d.%09d", s, ns)
 			x = strings.TrimSuffix(x, "000")
 			x = strings.TrimSuffix(x, "000")
 			out.write(`"`)

vendor/github.com/golang/protobuf/jsonpb/jsonpb_test.go

@@ -407,6 +407,7 @@ var marshalingTests = []struct {
 	{"Any with WKT", marshaler, anyWellKnown, anyWellKnownJSON},
 	{"Any with WKT and indent", marshalerAllOptions, anyWellKnown, anyWellKnownPrettyJSON},
 	{"Duration", marshaler, &pb.KnownTypes{Dur: &durpb.Duration{Seconds: 3}}, `{"dur":"3.000s"}`},
+	{"Duration", marshaler, &pb.KnownTypes{Dur: &durpb.Duration{Seconds: 100000000, Nanos: 1}}, `{"dur":"100000000.000000001s"}`},
 	{"Struct", marshaler, &pb.KnownTypes{St: &stpb.Struct{
 		Fields: map[string]*stpb.Value{
 			"one": {Kind: &stpb.Value_StringValue{"loneliest number"}},