title: Git rebase auto abort on conflict
body: <p>I would like to configure git in a way to get the best of these both options, which are unfortunately mutually exclusive:</p>
  <pre><code>[pull]
      ff = only
      rebase = true
  </code></pre>
  <p>Basically, I want to automatically rebase when pulling, but if there are conflicts, the rebase should be aborted.<br />
  This way, if I update in the background, my repository always stays in a valid state.</p>