title: Add current viewcontroller to navigationControllerStack
body: <p>okay, so I have 2 VC.</p>
  
  <p>From vc1 I move to vc2 using segue</p>
  
  <p>Now from vc2 I want to move to vc2 using the following code</p>
  
  <pre><code>let vc = storyboard?.instantiateViewController(withIdentifier: screenId)
          navigationController?.pushViewController(vc!, animated: true)
  </code></pre>
  
  <p>It's not working as VC2 wasn't added to navigation controller stack.</p>
  
  <p>I want to know how to add the VC2 to navigation controller stack programmatically.
  The thing is that I am using segue in some cases and pushing view controller in some other.</p>