Makes sharedstate.{cpp|h} a lot easier to read, and adding new shaders a one liner.
Releasing a Tilemap atlas into the pool on every map switch will blow out tons of smaller textures for very little gain, as atlas textures are already pretty much impossible to recycle anywhere but in new Tilemaps.
This was particularly nasty with the shorthand macros 'gState' and 'glState'. The former is now 'shState'.