It was originally (without any comment to this effect, either in the
code or the commit message) just the list of offset-zones
corresponding to known Windows zones' offsets, augmented to include
each whole hour offset out to ±14 hours. Absent documentation, of
course, this was not maintained.
Added the four offset zones implied by that, that hadn't been added
when new entries joined the Windows IDs with novel offsets. Check,
after scanning CLDR for Windows data, that this has been kept up to
date. Updated the generated data.
Change-Id: I3cf3932c320876f7f2f74840d8c3951be49cfe70
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>