title: How to remove a user from all rosters in Ejabberd
body: <p>I want to delete a chat account and at the same time :</p>
  
  <ol>
  <li>Delete his roster</li>
  <li>Delete him from all of his friends rosters</li>
  </ol>
  
  <p>How can i do this?</p>
  
  <p>I have tried the various options of ejabberdctl. I can unregister a user, and even purge his roster, but I cant find a way to remove him from other rosters.</p>
  
  <p>PS : All my users are currently on one server/host</p>