Support device media queries
Support orientation media queries
Listen for status bar orientation notifications instead of device orientation notifications
Remove registered objects list, just walk all visible views

In my timing tests, walking the visible views was about the same amount of time as using registered objects. Since using registered objects was causing memory leaks and did not handle all stylesheet changes, it made sense to remove them.
Merge branch 'media-queries'

Conflicts:
	NUI/Core/NUIRenderer.m