Git 先创建项目后提交到仓库[Note about fast-forwards]

1. 初始化： 

   git init

2. 把项目添加到本地仓储：

   git add .
   git commit -am "备注"

3. 添加远程地址

   git remote add origin https://gitee.com/xxx/xxx.git

4. 本地分支和远程分支  建立连接

   git branch --set-upstream-to=origin/master master

5. 因为远程仓库是刚创建的，本地仓库和远程仓库有不同的开始点【没有共同的commit】，需要拉取代码

   git pull origin master --allow-unrelated-histories

6. 异常就是由【4/5】导致的

   $ git push
   To https://gitee.com/xxx/xxx.git
    ! [rejected]        master -> master (non-fast-forward)
   error: failed to push some refs to 'https://gitee.com/xxx/xxx.git'
   hint: Updates were rejected because the tip of your current branch is behind
   hint: its remote counterpart. Integrate the remote changes (e.g.
   hint: 'git pull ...') before pushing again.
   hint: See the 'Note about fast-forwards' in 'git push --help' for details.