title: I can't delete a remote master branch on git
body: <p>I need to delete a master branch, but it's proving to be hard.  I just want to clean that branch out and start new.  I am deleting from the dev branch.  I want master on GitHub to be clean.</p>
  
  <pre><code> # git push origin --delete master
  
  &gt; To https://github.com/mymasterb.git  ! [remote rejected] master
  &gt; (deletion of the current branch prohibited) error: failed to push some
  &gt; refs to 'https://github.com/mymaster.git'
  </code></pre>
  
  <p>How do I quite simply start my master with a fresh slate?</p>