refactor: update of `Options.lua` to take advantage new `SavedVarRegistry`

[juemrami]

In this PR:

• moved around local helpers & public interfacing options to be colocated
• the hack around issues #200, #147, #57, has been removed (no longer needed)
• connected a couple of edge case setting updates to the new SavedVar system
  • EnableGroup toggling the approriate tabs.
  • TimeOut duration clamped above 60
  • ChatStyle/CompactStyle mutual exclusivity