use clipboard package to handle clipboard stuff

vendor/github.com/atotto/clipboard/clipboard.go

@@ -0,0 +1,20 @@
+// Copyright 2013 @atotto. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package clipboard read/write on clipboard
+package clipboard
+
+// ReadAll read string from clipboard
+func ReadAll() (string, error) {
+	return readAll()
+}
+
+// WriteAll write string to clipboard
+func WriteAll(text string) error {
+	return writeAll(text)
+}
+
+// Unsupported might be set true during clipboard init, to help callers decide
+// whether or not to offer clipboard options.
+var Unsupported bool