Allow User to provide a file name instead of static name

Hmm, this isn't quite what I meant. Go ahead and leave the notification registration where it was in `init_internal`, but have it call a method that first checks whether `enabled` is YES before attaching the gesture. It would probably be better to also have the window created within that method as well, but only if `enabled` is YES. That way there is never a separate window until we are sure the menu is enabled.