title: Multiple file versions in git-lfs
body: <p>I'm trying to estimate the storage requirements for my project on GitHub and have a few questions about how git-lfs stores multiple versions of files:</p>
  
  <ul>
  <li>Are multiple versions of files stored by git-lfs?</li>
  <li>If so, will every change to a file result in the complete file being replicated, or are only differences stored? </li>
  <li>Will all versions count towards the quota on github?</li>
  <li>Is there any way to control how many versions are kept?</li>
  </ul>