title: For Ruby on Rails project pull request, git push to my fork failing
body: <p>I made fixes and tests, <code>git commit -a</code>, updated my branches and now I'm trying to push to a GitHub fork I had previously made:</p>
  
  <pre><code>vagrant@rails-dev-box:~/rails$ git push mine my_fix
  Username for 'https://github.com': myusername
  Password for 'https://myusername@github.com':
  To https://github.com/myusername/rails.git
   ! [rejected]        my_fix -&gt; my_fix (non-fast-forward)
  error: failed to push some refs to 'https://github.com/myusername/rails.git'
  To prevent you from losing history, non-fast-forward updates were rejected
  Merge the remote changes (e.g. 'git pull') before pushing again.  See the
  'Note about fast-forwards' section of 'git push --help' for details.
  </code></pre>
  
  <p>I'm guessing the reason for this issue is the fork is a little outdated (by a week maybe). I've made other pushes to the fork though that I don't want to lose. What do I do here?</p>