title: git push error due to non-existent large file
body: <p>I keep getting the same result when trying to push to git:</p>
  
  <pre><code>Counting objects: 78, done.
  Delta compression using up to 4 threads.
  Compressing objects: 100% (67/67), done.
  Writing objects: 100% (71/71), 36.29 MiB | 637.00 KiB/s, done.
  Total 71 (delta 39), reused 0 (delta 0)
  remote: error: GH001: Large files detected.
  remote: error: Trace: 7e446266168df8617c74b6a319ec4538
  remote: error: See http://git.io/iEPt8g for more information.
  remote: error: File lecture_2_github_io_numpy_pandas/data/cup98LRN.txt is 111.74 MB; this exceeds GitHub's file size limit of 100 MB
  To git@github.com:mas-dse/gbrock.git
   ! [remote rejected] master -&gt; master (pre-receive hook declined)
  error: failed to push some refs to 'git@github.com:mas-dse/gbrock.git'
  </code></pre>
  
  <p>The thing is, that txt file does not exist any more. I made changes to the ipython notebook to have that text file removed. Saved the notebook. Added the changes to git. Committed the changes. Then try to do a push to git, but it does not want to work. </p>
  
  <p>I can't use the:</p>
  
  <pre><code>git rm --cached 'file' 
  </code></pre>
  
  <p>Because that file does not exist any more. I have no clue what do. Any help would be much appreciated.</p>