title: "Back" button is missing in my navigation controntroller
body: <ul>
  <li>I create a standard navigation controller</li>
  <li>I do Editor > "embed in" navigation controller</li>
  <li>I create segue from mother controller to navigation controller, name it</li>
  <li><p>I perform a custom segue:</p>
  
  <p>performSegueWithIdentifier(CONSTANTS.SegueListMessagesToMessages, sender:view)</p></li>
  </ul>
  
  <p>Great, it pops up.</p>
  
  <p>However, the child view doesn't have a back button on the navigation controller bar.</p>
  
  <p>I guess I could add a bar button item...but I can't find the Chevron that Apple uses for "Back" in the symbols. Why can't the back button be there automatically?</p>