This is a rather naive implementation, but serves as a first pass at
determining the GMT offset for a time zone at a particular point in
time. This implementation ignores DST (because we are not parsing any
RULE entries yet), and ignores any offset patterns of the form "Mon>4"
or "lastSun".
For example, generate "Etc/GMT+12" as "Etc_GMT_Ahead_12" (instead of as
"Etc_GMT_P12"). A little clearer what the name means without having to
know off-hand what "P" was representing.
When compiled using clang, an ambiguity error is detected between
`class AK::Time` aliased to `::Time` and the `struct ::Time` provided
in `GenerateTimeZoneData.cpp`. Solve this by moving most of the code in
an anonymous namespace.
The IANA Time Zone Database contains data needed, at least, for various
JavaScript objects. This adds plumbing for a parser and code generator
for this data. The generated data will be made available by LibTimeZone,
much like how UCD and CLDR data is available through LibUnicode.
