title: How to clean a remote GIT repository?
body: <p>I've a hosted GIT repository with limited disk space available but connected with a RedMine system.
  I'm packaging some software and pushing and pulling on the repository, I'm run out of space. Now I need to clean (the packages are note needed anymore).
  How can I delete these packages from the remote repository history, considering that I cannot re-create the repository (it's too strictly linked to RedMine)?</p>