Added swipe gesture recognizer to return to front view

PKRevealControllerRecognizesResetOnSwipeKey and
recognizesResetSwipeOnSideView default to YES. UISwipeGestureRecognizer
is added to left or right views as another option to return to the
front view.
Removed unnecessary NSLogs in swipe methods

NSLog's were unneeded - used for testing purposes previously.
Added rounded corners property to PKRevealControllerContainerView

Access works the same way as shadows.