title: Write a git alias for fast forward that works in any tracking branch?
body: <p>I'd like to create an alias to do the following:</p>
  
  <p>Working in <code>master</code>, I would like <code>git ff</code> to perform <code>git merge --ff-only origin/master</code>.  But I want the same alias, when run in <code>maint</code> to perform <code>git merge --ff-only origin/maint</code>.  Likewise for any other tracking branches.  Is this possible?</p>