This fixes the mathlib build, at least for me.
I didn't bother to fix code in e.g. raytrace or vgui_controls, so things
are almost certainly still broken in there.
* Fixed a variety of server browser issues with mods based on this SDK
* Fixed many warnings on various platforms
* Added source code for fgdlib and raytrace
* Updated many source files with the latest shared source from TF2.
OSX:
* Added support for Xcode 4.6
* Switched OSX builds to use Xcode instead of makefiles
* Moved libs from src/lib/osx32 to src/lib/public/osx32 or src/lib/common/osx32 to match windows better.
Linux:
* Moved libs from src/lib/linux32 to src/lib/public/linux32 or src/lib/common/linux32 to match windows better.