[tz] Rules for TZ+ database

[Paul Eggert]

Lester Caine wrote:
> 'some' end consumers do

Yes, absolutely.  We're trying to come up with a solution
that caters to the few consumers who really need to know what
time it was in Ft. Liard during the solar eclipse of June 10,
1964, without unduly burdening the far greater number of
consumers who who don't want to be burdened with information
that makes it more of a pain to select TZ settings
and that can hurt runtime performance.