* refactored model loading code based on code from dev-models
* support new model format V2 (without LOD levels)
* removed LOD levels support in CEngine and from model files
* preparations for new model format V3:
- support for multiple meshes in one model file
- support for saving crash spheres and shadow spots
- removed all direct dependencies on CEngine enum values
- quantized model rendering states to new flags and enums
Piotr Dziwinski