- cleaned up .gitignore.

This still contained a lot of data from the pre-CMake build setup for Windows. None of these paths is relevant anymore.

.gitignore

@@ -1,59 +1,26 @@
-/Debug
 *.ncb
 *.suo
 *.pdb
 *.ilk
 *.aps
-/fmodapi*/
-/Release
 /wadsrc_wad
 *.user
 /build
-/debug
-/release
-*/debug
-*/release
 /release_gcc
-/dumb/vc6/dumb_static/release
-/dumb/vc6/dumb_static/debug
-/dumb/vc6/dumb_static/x64
 /DOOMSTATS.TXT
 /src/gitinfo.h
-/src/sc_man_scanner.h
-/src/xlat/xlat_parser.c
-/src/xlat/xlat_parser.h
-/src/xlat/xlat_parser.out
-/src/zscript/zcc-parse.c
-/src/zscript/zcc-parse.h
-/src/zscript/zcc-parse.out
-/tools/*/debug
-/tools/*/release
-/tools/*/*.exe
-/tools/lemon/build
-/tools/re2c/build
-/tools/updaterevision/x64/
-/tools/zipdir/x64
 /wadsrc/*.pk3
-/build_vc2013
-/bzip2/x64/
 /disasm.txt
-/game-music-emu/x64/
-/gdtoa/x64/
-/jpeg-6b/x64/
-/lzma/x64/
-/zlib/x64/
-/build_vc2013_64bit
 /build_vc2015
 /build_vc2015-32
 /build_vc2015-64
 /build_vc2017-64
 /build
 /llvm
-/src/r_drawersasm.obj
-/src/r_drawersasm.o
 .vs
 /src/gl/unused
 /mapfiles_release/*.map
 .DS_Store
 /build_vc2017-32
 /build2
+/build_vc2019-64