title: Error when pull from GitHub
body: <p>I am trying to pull a project from GitHub, which I am collaborating on, but I receive the following error:</p>
  
  <blockquote>
    <p>your local changes to the following files would be overwritten by
    merge</p>
  </blockquote>
  
  <p>I have tried to merge by: 
  git mergetool {pathtofile}</p>
  
  <p>But it just respons with "File does not need merging".</p>
  
  <p>If I try to push my changes first I receive:</p>
  
  <pre><code>To prevent you from losing history, non-fast-forward updates were rejected.
  </code></pre>
  
  <p>What might I be missing?</p>