Fix going to wrong menu upon quit

The problem was, if you were in a time trial and quit, it wouldn't go
back to selecting your current time trial. But also if you were in a
custom level and quit, you would still be on the playerworlds menu.

The problem was twofold: first, I simply wasn't doing the custommode
check. But secondly, I couldn't use map.custommode directly, because
whenever you quit the game aggressively hardreset()s everything
immediately when you press ACTION.

There's probably a good reason for that aggressive hardreset(), so I
won't touch that hardreset() in any way. Instead, I had to introduce two
kludge variables wasintimetrial and wasincustommode to Game, and use
those to do the check proper.

desktop_version/src/Game.cpp

@@ -232,6 +232,9 @@ void Game::init(void)
     customleveltitle="";
     createmenu(Menu::mainmenu);
 
+    wasintimetrial = false;
+    wasincustommode = false;
+
     deathcounts = 0;
     gameoverdelay = 0;
     frames = 0;
@@ -1341,10 +1344,13 @@ void Game::updatestate()
             //Don't be stuck on the summary screen,
             //or "who do you want to play the level with?"
             //or "do you want cutscenes?"
-            if (!intimetrial)
+            //or the confirm-load-quicksave menu
+            if ((!wasintimetrial && !wasincustommode) || currentmenuname == Menu::quickloadlevel)
             {
                 returnmenu();
             }
+            wasintimetrial = false;
+            wasincustommode = false;
             state = 0;
             break;