Add transition to present ViewController with gesture.

[bfernandesbfs]

Hi guys,

Simulate swipe of Notification center, when user swipe of any orientation for sample, started transition to present second viewcontroller. the effect opposite PresentationControllerAnimator

[marcosgriselli]

Added a quick example on the BasePresentationController class (uncomment window?.rootViewController = BasePresentationViewController() from the AppDelegate to see it) for presenting a view controller interactively. It's swipe from the bottom to present and then swipe on the presented view controller to dismiss.