Update copyright date
Improve nested scroller drawing and responsiveness

 - Split the old scrollBoundary option into two: scrollBoundary
(handles exclusive scrolling/locking boundary) and
scrollResponseBondary (handles when updates are drawn in response to
touches)
 - Set the default scrollResponseBoundary to 1, and add support for
drawing updates while still able to cancel the scroll if another
scroller gains scroll lock
 - Improve IE 10 nested scrollers.  (Known issue: pointer capture is
cancelled on one element if another element captures pointers, causing
problems in nested scrollers)
 - Add boundary examples to the Gallery scrollers example, and improve
the example