Add github.com/chai2010/gettext-go dependency

vendor/github.com/chai2010/gettext-go/gettext/local.go

@@ -0,0 +1,34 @@
+// 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 gettext
+
+import (
+	"os"
+	"strings"
+)
+
+func getDefaultLocale() string {
+	if v := os.Getenv("LC_MESSAGES"); v != "" {
+		return simplifiedLocale(v)
+	}
+	if v := os.Getenv("LANG"); v != "" {
+		return simplifiedLocale(v)
+	}
+	return "default"
+}
+
+func simplifiedLocale(lang string) string {
+	// en_US/en_US.UTF-8/zh_CN/zh_TW/el_GR@euro/...
+	if idx := strings.Index(lang, ":"); idx != -1 {
+		lang = lang[:idx]
+	}
+	if idx := strings.Index(lang, "@"); idx != -1 {
+		lang = lang[:idx]
+	}
+	if idx := strings.Index(lang, "."); idx != -1 {
+		lang = lang[:idx]
+	}
+	return strings.TrimSpace(lang)
+}