Added support for delegated events to the pointer events polyfill (pointerdown, pointermove and pointerup only - for now) and the pointer gestures (press and sweep). Created two utility methods that prevent double events when using the jQuery event special "add" and "remove" methods, which provide us the delegated selector (the "setup" and "teardown" special event method doesn't).
Updated comments for readability.
Ensure the target is provided, which it is not if something else triggers a touchend event manually.