Added support for TILB files to contain how many cells wide and tall the map is - which is needed in games that want to adjust their camera bounds without having to iterate through all tiles.
Used the VersionNumber in TILB for the first time - this should make it so old files still work just fine but new data can be added easily.
Renamed TiledMapSave.width and height to Width and Height (capitalized to C#ify them).