参考链接:http://www.cocoachina.com/ios/20151120/14258.html

http://www.jianshu.com/p/88c1b65e3ddb

http://www.cnblogs.com/levilinxi/p/4296712.html

http://www.cocoachina.com/appstore/20160310/15632.html

http://www.cocoachina.com/ios/20170214/18681.html

iOS国际化技巧