+map images

+BigSprite and BigTexture classes to split large textures into smaller ones, required because the videocard can have a limit on the dimensions of the texture.

+ContentManager maps content to a resource id and stores resources that are shared between game objects

+SceneNode to implement scene graph

+World class to represent the game world, uses empty scene nodes under the scene root to split the scene into layers, curently contains logic to allow scrolling the map using WSAD keys.