preview handling rework
correct menu selection for current video resolution
more preview changes and fixed video orientation
fixed video-size preference storage and preview aspect ratio handling
dont call setPreviewSize in CameraActivity

will be done from SettingsWidget afterwards
always call notifyPreviewSize
release camera on mode switch

This may be device specific
At least on find5 we must release and reconnect
the camera on mode switching between still and video mode
Moar fixes, on top of maxwen's changes