title: How to prevent group creation in GitLab
body: <p>I have setup GitLab 7.12 in my firm. But users start creating groups (and groups and groups ...) and it will become a total mess very soon.
  Does anyone know how to restrict groups creation to administrators of the platform ?</p>
  
  <p>The idea is to have people creating projects in their personal space, and reserving groups for official ones.</p>