Restructured to allow the use of multiple screens.
Changed MyGame to implement Game.
Moved the render, resize, ... logic of MyGame to a new class GameScreen. GameScreen will now function as the "main controller" for the running game.
Added an abstract class AbstractScreen, for basic shared handling of (mostly) menu-like screens.
Added a new class LoadoutScreen.
Merge branch 'development' into loadoutScreen
Merge branch 'development' into loadoutScreen
Set up a (very) basic first attempt at a menu.
Merge branch 'development' into loadoutScreen

Conflicts:
	Bullet-Inferno/src/se/dat255/bulletinferno/MyGame.java
Added a start button
Merge branch 'development' into loadoutScreen.

Conflicts:
	Bullet-Inferno/src/se/dat255/bulletinferno/MyGame.java
Merge branch 'development' into loadoutScreen
Merging loadoutScreen into development
Merge branch 'development' of https://github.com/Jokab/Bullet-Inferno into development