title: Dismissal of UIAlertController (best practice)
body: <p>When using UIAlertController like this:</p>
  
  <pre><code>var alert = UIAlertController(title: "Core Location", 
       message: "Location Services Disabled!", 
       preferredStyle: UIAlertControllerStyle.Alert)
  alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.Default, 
       handler: nil))
  self.navigationController.presentViewController(alert, animated: true, 
       completion: nil)
  </code></pre>
  
  <p>I noticed that the dismissal of the alert view is seemingly done automatically.
  Shouldn't the dismissal of a presented ViewController be done by the <strong>presenting</strong> ViewController via a delegate call?</p>