非常好的教材：
https://git-scm.com/book/zh/v2/起步-安装-Git
http://blog.jobbole.com/78960/
https://www.liaoxuefeng.com/wiki/0013739516305929606dd18361248578c67b8067c8c017b000/0013744142037508cf42e51debf49668810645e02887691000/
