Merge pull request #2 from brainchest/master

Infrastructure changes to start working with the projects
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
Merge branch 'master' of https://github.com/craftworkgames/CraftworkGUI
Fixing some layout issues. Mandatory root layout. More demo code.
Added an animated background to the demo.
Working on multi-screen demo.
Merge in from master to fork for the latest Screen manager changes