[tz] Dropping iso3166.tab

[Petr Machata]

Paul Eggert <eggert at cs.ucla.edu> writes:

> (1) Remove iso3166.tab.  Others can take up its maintenance if they
> like.

FWIW, I've been pointed to the following project:
  https://github.com/mike-fabian/langtable

see in particular this file:
  https://raw.github.com/mike-fabian/langtable/master/data/territories.xml

I'm being told that that's what Anaconda (the installer for Fedora and
RHEL) should use in future.  Unfortunately it lacks the "comment" part
of zone.tab, and it also contains quite a bit more than zone mapping.

Thanks,
PM