The KeyValues class belongs here. Also reimplemented most loading methods for KeyValues, and adjusted the VPK building code to account for it. Pointers to the engine's implementation of KeyValues have been moved to a separate header ('keyvalues_iface.h'), as this allows external tools code to utilize the standalone KeyValues class implementation. Playlist utilities are completely separated from the KeyValues header; these have nothing to do with KeyValues other than manipulating a global KeyValues object for the playlists, and thus have been named as such and moved to rtech/playlists.
Work in progress; does not compile!
Moved script registration function to static gamedll libs instead, and used a pointer callback approach for calling them to avoid duplicate symbols during linkage.
Reason parameters are optional. For scripts, to use the default message, pass in an empty string. The function for the script system should be centralized soon to avoid more duplicate code.
Properly decouple squirrel and game code. This makes it easier to reverse engineer more of this squirrel system, and to compile them as individual libraries later on when moving to CMake to significantly decrease compile times.
