vendor: update all dependencies except Azure SDK

The Azure SDK doesn't support Go 1.5 anymore. We can't upgrade it until
Go 1.8 comes out.

vendor/github.com/mattn/go-colorable/colorable_others.go

@@ -7,6 +7,7 @@ import (
 	"os"
 )
 
+// NewColorable return new instance of Writer which handle escape sequence.
 func NewColorable(file *os.File) io.Writer {
 	if file == nil {
 		panic("nil passed instead of *os.File to NewColorable()")
@@ -15,10 +16,12 @@ func NewColorable(file *os.File) io.Writer {
 	return file
 }
 
+// NewColorableStdout return new instance of Writer which handle escape sequence for stdout.
 func NewColorableStdout() io.Writer {
 	return os.Stdout
 }
 
+// NewColorableStderr return new instance of Writer which handle escape sequence for stderr.
 func NewColorableStderr() io.Writer {
 	return os.Stderr
 }

vendor/github.com/mattn/go-colorable/colorable_windows.go

@@ -75,6 +75,7 @@ type Writer struct {
 	oldpos  coord
 }
 
+// NewColorable return new instance of Writer which handle escape sequence from File.
 func NewColorable(file *os.File) io.Writer {
 	if file == nil {
 		panic("nil passed instead of *os.File to NewColorable()")
@@ -90,10 +91,12 @@ func NewColorable(file *os.File) io.Writer {
 	}
 }
 
+// NewColorableStdout return new instance of Writer which handle escape sequence for stdout.
 func NewColorableStdout() io.Writer {
 	return NewColorable(os.Stdout)
 }
 
+// NewColorableStderr return new instance of Writer which handle escape sequence for stderr.
 func NewColorableStderr() io.Writer {
 	return NewColorable(os.Stderr)
 }
@@ -357,6 +360,7 @@ var color256 = map[int]int{
 	255: 0xeeeeee,
 }
 
+// Write write data on console
 func (w *Writer) Write(data []byte) (n int, err error) {
 	var csbi consoleScreenBufferInfo
 	procGetConsoleScreenBufferInfo.Call(uintptr(w.handle), uintptr(unsafe.Pointer(&csbi)))

vendor/github.com/mattn/go-colorable/noncolorable.go

@@ -5,15 +5,18 @@ import (
 	"io"
 )
 
+// NonColorable hold writer but remove escape sequence.
 type NonColorable struct {
 	out     io.Writer
 	lastbuf bytes.Buffer
 }
 
+// NewNonColorable return new instance of Writer which remove escape sequence from Writer.
 func NewNonColorable(w io.Writer) io.Writer {
 	return &NonColorable{out: w}
 }
 
+// Write write data on console
 func (w *NonColorable) Write(data []byte) (n int, err error) {
 	er := bytes.NewReader(data)
 	var bw [1]byte