Removed MFC dependencies to compile with VS2012EE

Removed MFC libs from linker input, had to include Windows header in
doom.rc to get language enums/defines, and rewrote Sys_GetVideoRam to
not use MFC smart pointer helper objects and BSTRs (obsolete).
Sys_GetVideoRam tested independently of Doom3BFG, confirmed working on
my machine and passed analyze (VS2012EE) with no issues/warnings raised.
Commit has not been tested with Doom3BFG, use at your own risk.