90 degree rotation flag is now supported (remove comment about it being unsupported)
Should add the following:
- 3-bit property "palette" in Tile descriptor
- TLN_SetGlobalPalette() to set the palettes used by "palette" property. 8 global palettes available
- TLN_GetTilemapTiles() to get pointer to internal tilemap data
- Position getters for layers and sprites: TLN_GetSpriteX()... TLN_GetLayerY()
- Getter for global palette: TLN_GetGlobalPalette()