Don't go to main menu when exiting to menu

This also replaces some createmenu()s with returnmenu()s as needed even
when said createmenu()s already didn't go to the main menu.

Now when you exit the level editor, you'll be selecting the "level
editor" option in "play levels", and if you exit from a level you'll
still be selecting that level in the levels list.

Furthermore, regardless of what you're exiting, your cursor position
will be remembered.

desktop_version/src/editor.cpp

@@ -3455,7 +3455,10 @@ void editorlogic()
         map.nexttowercolour();
         ed.settingsmod=false;
         graphics.backgrounddrawn=false;
-        game.createmenu(Menu::mainmenu);
+        //Do returnmenu twice because we have two menus:
+        //the main editor menu and the confirm save&quit menu
+        game.returnmenu();
+        game.returnmenu();
     }
 }