MoGraph documentation and other updates

Update PhotoGallery example documentation
http://jira.mosync.com/browse/MOSYNC-3288

Add documentation for MoGraph:
http://jira.mosync.com/browse/MOSYNC-3281

Make new screenshots for ScreenOrientation example:
http://jira.mosync.com/browse/MOSYNC-3292

Doc: Release notes MoSync SDK 3.3:
http://jira.mosync.com/browse/MOSYNC-3139