backgrounds
Merge branch 'develop' of https://github.com/gsalgun/GreedyUSO into develop

Conflicts:
	core/target/classes/GreedyUSO/core/view/GameScreen$1.class
	core/target/classes/GreedyUSO/core/view/GameScreen.class
	desktop/src/main/java/GreedyUSO/java/GameDesktop.java
	desktop/target/classes/GreedyUSO/java/GameDesktop.class