SenchaTouch 2.2 release and WP8 support

Update to RC of ST2.2 (#100) and add initial support for WP8 (#99). 

SenchaTouch upgrade was via automatic upgrade facility (via intermediate upgrade to RC version).

PhoneGap build does not support WP8 yet (local build instead), not using WP8 theming, icons don't work, hardware back button not working.