http://benjsicam.me/blog/how-to-setup-eclipse-git-plugin-egit-for-github-part-1-tutorial/
http://benjsicam.me/blog/how-to-setup-eclipse-git-plugin-egit-for-github-part-2-tutorial/
以及安装插件速度慢的解决方案：
http://blog.csdn.net/dracotianlong/article/details/24015531