代码工程复制一份后，最好清空之前的所有commit记录
1.Checkout
git checkout --orphan latest_branch
2. Add all the files
git add -A
3. Commit the changes
git commit -am "project init."
4. Delete the branch
git branch -D master
5.Rename the current branch to master
git branch -m master
6.Finally, force update your repository
git push -f origin master