Prevent turning on invincibility/slowdown in in-game options menu

Would've been the easiest exploit ever! But I gotta patch it.

desktop_version/src/Game.cpp

@@ -7147,8 +7147,8 @@ void Game::createmenu( enum Menu::MenuName t, bool samemenu/*= false*/ )
         option("animated backgrounds");
         option("screen effects");
         option("text outline");
-        option("invincibility");
-        option("slowdown");
+        option("invincibility", !ingame_titlemode || !inspecial());
+        option("slowdown", !ingame_titlemode || !inspecial());
         option("load screen");
         option("room name bg");
         option("return");