* Move render utils to dedicated file.
* Implement more render/mesh utils.
* Added structure for OverlayTriangle_t, OverlaySweptBox_t and OverlayCapsule_t.
OverlayCapsule_t has been modified to accommodate the size in r5 (2 new vectors).
SourceSDK mathlib port with light modifications.
Renamed Vector to Vector3D (to avoid confusion with std::vector (declared as vector) and Vector2D/Vector4D).
Moved logging functions to dbg.h (tier0) and export them from the dll.
Added additional functions for checking bad pointers (debug only!).
Reduced output code size.
* Improve ConVar class (fixed several bugs).
* Hook CEngineAPI::ModInit() and set m_bRestrictServerCommands from there.
* Disable unused ConVar's and purge unused ConCommands in CEngineAPI::ModInit() for dedicated.
* Small relocation of malloc related signatures.
