[modified] TiledMapPacker and TileAtlas so that tile sets can be shared between maps. TiledMapPacker now takes an directory of maps instead of a single map as an argument.
[modified] TileMapRenderer (renamed from TiledMapRenderer) now takes a block width in tiles instead of pixels, began decoupling from Tiled (TileAtlas needs a few more changes for it to be complete)
[fixed] TileMapRenderer.render y coordinate matches the Tiled and camera coordinates
[modified] Test files to match changes to TiledMapPacker, TileAtlas, and TileMapRenderer