Add github.com/chai2010/gettext-go dependency

vendor/github.com/chai2010/gettext-go/gettext/plural/doc.go

@@ -0,0 +1,36 @@
+// Copyright 2013 ChaiShushan <chaishushan{AT}gmail.com>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package plural provides standard plural formulas.
+
+Examples:
+	import (
+		"code.google.com/p/gettext-go/gettext/plural"
+	)
+
+	func main() {
+		enFormula := plural.Formula("en_US")
+		xxFormula := plural.Formula("zh_CN")
+
+		fmt.Printf("%s: %d\n", "en", enFormula(0))
+		fmt.Printf("%s: %d\n", "en", enFormula(1))
+		fmt.Printf("%s: %d\n", "en", enFormula(2))
+		fmt.Printf("%s: %d\n", "??", xxFormula(0))
+		fmt.Printf("%s: %d\n", "??", xxFormula(1))
+		fmt.Printf("%s: %d\n", "??", xxFormula(2))
+		fmt.Printf("%s: %d\n", "??", xxFormula(9))
+		// Output:
+		// en: 0
+		// en: 0
+		// en: 1
+		// ??: 0
+		// ??: 0
+		// ??: 1
+		// ??: 8
+	}
+
+See http://www.gnu.org/software/gettext/manual/html_node/Plural-forms.html
+*/
+package plural