* Promoted size types in CUtlBuffer to int64.
* Fixed bug where CUtlBuffer::GetPtr returns a 64bit pointer that was promoted from a 32bit integral type.
* Use int64/size_t for anything strlen, pointer subtraction, etc..
* Removed invalid structure alignment declarations.
* 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).