title: Git: get number of changed lines per day
body: <p>I'd like to make a diagram of added/removed/changed lines in a git repository per day and/or week. I do <em>not</em> want to count the number of commits.</p>
  
  <p>Is there a tool that can produce such charts (gitstats does not)? Or, with which git command I can produce an output which i could parse easily?</p>
  
  <p>Thank you!</p>