title: Capistrano not deleting old releases
body: <p>I'm aware of the <code>keep_releases</code> option in capistrano and I have this set in our deploy script.  The problem I'm having is I think more related to permission issues.  I tried running <code>cap deploy:cleanup</code> but I get a permission denied error when trying to delete directories inside <code>tmp/cache</code>.  I'm using fragment caching which is why I have lots of files inside <code>tmp/cache</code>.</p>
  
  <p>Can someone shed any light how to fix this issue?  I have to manually delete the folders in the server in order to clean up the releases folder.</p>