Cleanup
Use top srite margin
Experimenting with VAO
VAO Refactoring
More local/shared state refactoring
VAO refactoring coninued
More fractoring
fix memory leak
no need to publish Tile properties as we are using special tile-streaming format
One more step towards multilevel maps

* separate levels from map itself
* make maptile value object (also useful for future tarrain geometry shader)
Some tweaks
Use constant attribute locations