BackgroundGUI added

Awesome functional background GUI only supporting png files.
Tree changes (delete function)

Many bugs related to script and room windows.
Delete function partially added to delet resources from the folders.
RoomGUI

Provitional text editor for creating SGE rooms.
The text editor will be replaced so everything can be made on a visual
way.
Game template

The game template is the file that Stellar uses for creating the final
game based on the resources of the projects.
SGE added to data

the SGE file to use with your game.
Provitional example and updates

This is still a WIP but you can already start playing with it on
Windows.