CModelDef fixes uploaded.
This patch addresses two problems:
1) CModelDef loading performance
In order to make loading faster, had to change the format of cached binary model data. The new model cache files take a tiny bit more disk space, but in return they load several times faster and the loaded data takes less memory.
2) Complex dynamic objects in structs
One of the main perf hitters was a per-vertex (yes, per each vertex!) std::vector<float> for multiple UV's. This was replaced with 2x CVector2D UV0 & UV1.
Another one was an std::string for model prop points, which was replaced with a fixed size buffer m_Name[20] and with an additional m_NameLength.
The result: much better memory performance and usage for model loading.
In order for this to work, I had to change the version of the PMD (binary model cache) format to 4 and change the way models are saved to PMD. This may invalidate any existing model cache. Backwards compatibility for versions 1, 2, 3 is there.
