Issue #22065: Menus, unlike Menubottons, do not have a state option.
Since a new demo can now be loaded while one is running,
adjust loadfile to do the same cleanup as stopIt.

--HG--
branch : 3.4
Issue #22065: Remove the now unsed configGUI menu parameter and arguments.

--HG--
branch : 3.4
The webbrowser module now uses subprocess's start_new_session=True rather
than a potentially risky preexec_fn=os.setsid call.

--HG--
branch : 3.4