使用git push是，采用以下步骤：
git init
git add README.md
git commit -m "first commit"
git remote add origin https://github.com/focusor/focusor.github.io.git
git push -u origin master产生如下错误：
error: src refspec master does not match any.
error: failed to push some refs to "xxxxxxx"然后用如下方法解决了：
git add .
git commit -m "write your meaaage"之后push就成功了，具体原因是什么呢？
