title: willDisplayCell of UTTableView is not called
body: <p>I want to change the state of a cell in a TableView. I tried setting the state in "cellForRowAtIndexPath" method, but it did not work. Then I saw posts that said that in order to change the state of a cell one needs to use the delegate method "willDisplayCell". However, when I implemented the method it is not being called (I put a breakpoint which was not called)</p>
  
  <pre><code>func tableView(tableView: UITableView, willDisplayCell cell: UITableViewCell, forRowAtIndexPath indexPath: NSIndexPath) {
  
      cell.selected = true
  }
  </code></pre>
  
  <p>I tried also using "willDisplay" as it appears in Apple documentation, but that did not help. As a matter of fact, I tried any garbage instead of that string and nothing happens - the app compiles with no errors but the method is not being called.</p>
  
  <p>I know that the delegate of the tableView is working because other delegate methods, such as "didSelectRowAtIndexPath", are being called.</p>