Fixes for KineticScrollViews

1. Updates mousewheel to support Firefox and IE
2. KSV does not currently update the _currentTranslationX and _currentTranslationY properties, as such all kinds of horrible things happen when try to scroll a view that had either previously been scrolled or is currently scrolling. This version fixes that. Although I think the velocity calculations need a lot of love still.
3. Changes the scrollbar visibility behaviour so that they do not appear until the view actually scrolls. This is needed for any scrolling view with clickable elements.