title: How do you roll back to the previously deployed version with capistrano?
body: <p>I tried using &quot;cap rollback&quot; but I get the following error:</p>
  <blockquote>
  <p>$ cap rollback</p>
  <p>the task `rollback' does not exist</p>
  </blockquote>
  <p>Is there some additional setup that I need to do to get rollbacks to work?</p>