title: Swift: searchBar - how to change "Cancel" Button title
body: <p>I have UIViewController which adopted UISearchBarDelegate. And set its delegate to self with: resultSearchController.searchBar.delegate = self. It works fine I tested it with searchBarCancelButtonClicked method%</p>
  
  <pre><code>func searchBarCancelButtonClicked(searchBar: UISearchBar) {
          println("Сancel button tapped")
      }
  </code></pre>
  
  <p>I see "Сancel button tapped" in console. But I would like to change "Cancel" Button title and I don't know how. I tried with:</p>
  
  <pre><code>func searchBarTextDidBeginEditing(searchBar: UISearchBar) {      
          var barButton = UIBarButtonItem(title: "Button Title", style: UIBarButtonItemStyle.Done, target: self, action: "here")
          self.resultSearchController.searchBar.showsCancelButton = false
          self.resultSearchController.navigationItem.rightBarButtonItem = barButton
      }
  </code></pre>
  
  <p>But it doesn't work. Could you help me please?</p>