Add glitchrunner mode, in game options

Glitchrunner mode is intended to re-enable glitches that existed in
older versions of VVVVVV. These glitches were removed because they could
legitimately affect a casual player's experience. Glitches like various
R-pressing screwery, Space Station 1 skip, telejumping, Gravitron
out-of-bounds, etc. will not be patched.

desktop_version/src/Game.h

@@ -404,6 +404,7 @@ public:
     }
 
     bool over30mode;
+    bool glitchrunnermode; // Have fun speedrunners! <3 Misa
 
     bool ingame_titlemode;