Update time zone data files to tzdata release 2021e.

Update time zone data files to tzdata release 2021e.

DST law changes in Fiji, Jordan, Palestine, and Samoa.  Historical
corrections for Barbados, Cook Islands, Guyana, Niue, Portugal, and
Tonga.

Also, the Pacific/Enderbury zone has been renamed to Pacific/Kanton.
The following zones have been merged into nearby, more-populous zones
whose clocks have agreed since 1970: Africa/Accra, America/Atikokan,
America/Blanc-Sablon, America/Creston, America/Curacao,
America/Nassau, America/Port_of_Spain, Antarctica/DumontDUrville,
and Antarctica/Syowa.