title: Can't push to Git repository after merged branch
body: <p>I'm working on a Git repository, I had my branch (called jviotti) and my changes were merged to Master.
  Now, after commiting some changes, I found myself unabled to push to my branch.</p>
  
  <pre><code>$ git push origin jviotti
  To https://github.com/jorisbontje/pikapay-frontend.git
   ! [rejected]        jviotti -&gt; jviotti (non-fast-forward)
  error: failed to push some refs to 'https://github.com/jorisbontje/pikapay-frontend.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 tried then git pull:</p>
  
  <pre><code>$ git pull
  You asked me to pull without telling me which branch you
  want to rebase against, and 'branch.jviotti.merge' in
  your configuration file does not tell me, either. Please
  specify which branch you want to use on the command line and
  try again (e.g. 'git pull &lt;repository&gt; &lt;refspec&gt;').
  See git-pull(1) for details.
  
  If you often rebase against the same branch, you may want to
  use something like the following in your configuration file:
  
      [branch "jviotti"]
      remote = &lt;nickname&gt;
      merge = &lt;remote-ref&gt;
      rebase = true
  
      [remote "&lt;nickname&gt;"]
      url = &lt;url&gt;
      fetch = &lt;refspec&gt;
  
  See git-config(1) for details.
  </code></pre>
  
  <p>After browsing a similar question here at SO, i tried:</p>
  
  <pre><code>$ git pull origin master:jviotti
  From https://github.com/jorisbontje/pikapay-frontend
   ! [rejected]        master     -&gt; jviotti  (non-fast-forward)
  </code></pre>
  
  <p>I thought that would do the trick. What am I missing?</p>