This is Abstract Operation is required for the majority of
InstantConstructor's and InstantPrototype's methods.
The implementation is not entirely complete, (specifically 2 of the
underlying required abstract operations, ParseTemporalTimeZoneString
and ParseISODateTime are missing the required lexing, and as such are
TODO()-ed) but the majority of it is done.
Here we got our first Temporal object :^)
This patch adds the TimeZone object itself, its constructor and
prototype (currently empty), and a bunch of required abstract operations