title: Change transition to ONE ViewController in a UINavigationController while keeping back-swipe
body: <p>I'd like to implement a custom transition to ONE specific view-controller inside my UINavigationController.</p>
  <p>I can do so by providing my custom TransitionAnimator inside</p>
  <pre><code>func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationController.Operation, from fromVC: UIViewController, to toVC: UIViewController) -&gt; UIViewControllerAnimatedTransitioning?
  </code></pre>
  <p>or return nil otherwise and everything works fine! So the animation part is solved and working!</p>
  <p>BUT by returning nil for the times I want the default transition, I loose the back-swipe gesture.</p>
  <p>So my question is:
  How can I provide my custom transition to one specific VC, but keep everything else as is?!?</p>