Switch to v1.0.0 of github.com/MakeNowJust/heredoc (avoid SHA)

Signed-off-by: Davanum Srinivas <davanum@gmail.com>

vendor/github.com/MakeNowJust/heredoc/LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2014-2017 TSUYUSATO Kitsune
+Copyright (c) 2014-2019 TSUYUSATO Kitsune
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

vendor/github.com/MakeNowJust/heredoc/README.md

@@ -1,4 +1,6 @@
-# heredoc [![CircleCI](https://circleci.com/gh/MakeNowJust/heredoc.svg?style=svg)](https://circleci.com/gh/MakeNowJust/heredoc) [![Go Walker](http://gowalker.org/api/v1/badge)](https://gowalker.org/github.com/MakeNowJust/heredoc)
+# heredoc
+
+[![Build Status](https://circleci.com/gh/MakeNowJust/heredoc.svg?style=svg)](https://circleci.com/gh/MakeNowJust/heredoc) [![GoDoc](https://godoc.org/github.com/MakeNowJusti/heredoc?status.svg)](https://godoc.org/github.com/MakeNowJust/heredoc)
 
 ## About
 
@@ -15,8 +17,6 @@ $ go get github.com/MakeNowJust/heredoc
 ```go
 // usual
 import "github.com/MakeNowJust/heredoc"
-// shortcuts
-import . "github.com/MakeNowJust/heredoc/dot"
 ```
 
 ## Example
@@ -26,11 +26,11 @@ package main
 
 import (
 	"fmt"
-	. "github.com/MakeNowJust/heredoc/dot"
+	"github.com/MakeNowJust/heredoc"
 )
 
 func main() {
-	fmt.Println(D(`
+	fmt.Println(heredoc.Doc(`
 		Lorem ipsum dolor sit amet, consectetur adipisicing elit,
 		sed do eiusmod tempor incididunt ut labore et dolore magna
 		aliqua. Ut enim ad minim veniam, ...
@@ -45,8 +45,7 @@ func main() {
 
 ## API Document
 
- - [Go Walker - github.com/MakeNowJust/heredoc](https://gowalker.org/github.com/MakeNowJust/heredoc)
- - [Go Walker - github.com/MakeNowJust/heredoc/dot](https://gowalker.org/github.com/MakeNowJust/heredoc/dot)
+ - [heredoc - GoDoc](https://godoc.org/github.com/MakeNowJust/heredoc)
 
 ## License
 

vendor/github.com/MakeNowJust/heredoc/heredoc.go

@@ -1,24 +1,31 @@
-// Copyright (c) 2014-2017 TSUYUSATO Kitsune
+// Copyright (c) 2014-2019 TSUYUSATO Kitsune
 // This software is released under the MIT License.
 // http://opensource.org/licenses/mit-license.php
 
 // Package heredoc provides creation of here-documents from raw strings.
 //
 // Golang supports raw-string syntax.
+//
 //     doc := `
 //     	Foo
 //     	Bar
 //     `
+//
 // But raw-string cannot recognize indentation. Thus such content is an indented string, equivalent to
+//
 //     "\n\tFoo\n\tBar\n"
+//
 // I dont't want this!
 //
 // However this problem is solved by package heredoc.
+//
 //     doc := heredoc.Doc(`
 //     	Foo
 //     	Bar
 //     `)
+//
 // Is equivalent to
+//
 //     "Foo\nBar\n"
 package heredoc
 
@@ -33,7 +40,7 @@ const maxInt = int(^uint(0) >> 1)
 // Doc returns un-indented string as here-document.
 func Doc(raw string) string {
 	skipFirstLine := false
-	if raw[0] == '\n' {
+	if len(raw) > 0 && raw[0] == '\n' {
 		raw = raw[1:]
 	} else {
 		skipFirstLine = true