Drop jQuery usage in responsive_menu.config.js

I think we can probably convert the existing javascript to vanilla js and drop the dependency on jQuery. This would be useful for any theme that doesn't use or need jQuery.

I believe the mmenu now has swipe gestures built in (need to test) so in theory the hammerswipe code and dependency can be dropped.

The new setting and options merge is using jquery's $.extend at the moment but probably Object.assign would work too.