* Only draw tiles that actually exist for each tileset/layer combination
* Set baseVertex and startIndex based on the number of draw calls and tiles per call
* First commit of separate map renderer code
* Only override on mono (linux)... not sure why this is needed, will look into later
* Updated test data for unittest
* Fixed layer transparency not working
* Couple of small changes
* Initial commit of separate Tiled rendering code
* Fixed bug causing last tile of each group not to draw
* Adding unit tests for FullMapRenderer and TiledTileset
* Fixed depth calculation bug when a map consists of only one layer
* Added level05.tmx to test isometric left-up rendering
