For example, LibJS will need to parse date strings of the form:
Wed Dec 31 1969 19:00:00 GMT-0500 (Eastern Standard Time)
This string contains both the time zone offset (-05:00) and a display
name for the time zone (Eastern Standard Time). Because we will already
handle time zone adjustments when we handle the offsets, we will want to
just skip the time zone name. This patch will let us use a format string
of the form "GMT%z (%+)" to do so.
LibCore currently cannot depend on LibTimeZone directly. All build-time
code generators depend on LibCore, so there'd be a circular dependency:
LibCore -> LibTimeZone -> GenerateTZData -> LibCore.
So to support parsing time zone names and applying their offsets, add a
couple of weakly-defined helper functions. These work similar to the way
AK::String declares some methods that LibUnicode defines. Any user who
wants to parse time zone names (from outside of LibCore itself) can link
against LibTimeZone to receive full support.
