git刪除所有歷史提交記錄，只留下最新的乾淨程式碼

1.Checkout

   git checkout --orphan latest_branch

2. Add all the files

   git add -A

3. Commit the changes

   git commit -am "commit message"


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