title: GitLab not able to sync fork
body: <p>I recently installed GitLab, however, I can't figure out how to use forks properly. I have the following versions installed:</p>
  
  <pre><code>GitLab 7.7.1
  GitLab Shell 2.4.1
  GitLab API v3
  Ruby 2.1.4p265
  Rails 4.1.1
  </code></pre>
  
  <p>I have found out the URL for forks (by creating another user and adding it to the project, but it doesn't show up in the GUI on own projects, link <code>http://server.com/&lt;user&gt;/&lt;repo&gt;/fork/new</code> works though), and once a fork has been made, it is not possible to sync the fork. At least, there's nothing I can find on Google nor the documentation for GitLab, but it is mentioned in changelogs at places or issues that apparently have been accepted (can't find the source anymore though).</p>
  
  <p>Can anyone explain me how forking works and how I can sync the fork once the original repository has been updated?</p>