Create 2 properties to disable closing pan and tap gesture

[eikebartels]

I create

closingPanGestureEnabled and closingTapGestureEnabled

and there logic to disable the closing

[colincameron]

+1

Without the ability to disable the closing pan gesture, swipe-to-delete on table view cells within the drawer is impossible.

[colincameron]

I was having trouble with this, as setting closingPanGestureEnabled to false actually prevented any user interaction with the mainViewController's view, regardless of the drawer state.

I've submitted #87 which overcomes this by taking a different approach.

[timusus]

Possibly superseded by #87