title: How to pop current view controller (non modal) and go back to previous one?
body: <p>I am trying to use a custom back button on my View Controller in Objective-C to pop the current view controller so that i can go back to previous controller.
  All the controllers are just view controllers and are not modally presented.
  How do I programmatically pop the current view controller (non modal) and go back to previous one?</p>