Fixes quest UI opening and closing after WoD.

Done by no longer trying to entirely replace the blizzard UI, but rather replacing
it only when "L" (Toggle Quest).  When Carbonite window is shown, we no longer try to
hide/replace the default UI which is now tightly coupled with the mapping UI.
Map toggles toggle the map. Quest toggle changes visibility of Carbonite quest UI.
Never do the two interact anymore.

This is how I chose to fix the current state of it not working.  It is a change from how Carb used to work (entirely replacing the quest UI), but I kind of like how I can still easily access the blizzard one and it has the bonus of simplifying the code considerably.
If you are heading a different direction with it, though, I certainly get that!