武翔

fix bug 101

1 git is a distributed version control system. 1 git is a distributed version control system.
2 -git is free software distributed under the GPL. 2 +git is a free software distributed under the GPL.
3 git has a mutable index called stage. 3 git has a mutable index called stage.
4 git tracks changes of files. 4 git tracks changes of files.
5 <<<<<<< HEAD 5 <<<<<<< HEAD
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