Removed screens and screen manager,
added support for not using a texture atlas,
renamed some properties and methods (breaking changes sorry),
changed the way the GUI system is created,
moved rendering and content loading to a draw and input manager
Fixing some layout issues. Mandatory root layout. More demo code.
Added an animated background to the demo.
Added support for WP8

- New project files + solution file for WP
- New demo project for WP8
- Texture load support from within XAP
- Touch support
- Added MonoGame v3.2 libraries to support portrait mode
Merge in from master to fork for the latest Screen manager changes
Merge pull request #3 from brainchest/master

Support for WP8