http://www.jianshu.com/p/db74e673e43c
http://blog.csdn.net/yzzky/article/details/44650825
http://blog.csdn.net/xiao__gui/article/details/36643949
https://github.com/google/protobuf/releases
http://blog.csdn.net/gaowenhui2008/article/details/55044704