Add beginnings of new cr command

go/src/infra/tools/cr/lib/terminal/terminal.go

Index: go/src/infra/tools/cr/lib/terminal/terminal.go
diff --git a/go/src/infra/tools/cr/lib/terminal/terminal.go b/go/src/infra/tools/cr/lib/terminal/terminal.go
new file mode 100644
index 0000000000000000000000000000000000000000..7ef0eb041b42e464a30fc4ef55c20ca6f4bd2b69
--- /dev/null
+++ b/go/src/infra/tools/cr/lib/terminal/terminal.go
@@ -0,0 +1,40 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Package terminal provides utilities for printing to and reading user input
+// from an interactive terminal.
+package terminal
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+var showDebug = false
+
+func ToggleDebug() {
+	showDebug = !showDebug
+}
+
+func SetDebug(show bool) {
+	showDebug = show
+}
+
+func Print(format string, args ...interface{}) {
+	fmt.Printf(format, args)
+}
+
+func Debug(format string, args ...interface{}) {
+	if showDebug {
+		fmt.Printf(format, args)
+	}
+}
+
+func Prompt(prompt string) string {
+	fmt.Print(prompt)
+	reader := bufio.NewReader(os.Stdin)
+	text, _ := reader.ReadString('\n')
+	return text
+}