Obsolete historic tz change for Libya; bug in Mexico comment

[Paul Eggert]

Jesper Norgaard Welen <jnorgard at prodigy.net.mx> writes:

> Therefore I suggest that the timezone rule be corrected to
> Rule	Libya	1987	1989	-	Oct	 1	0:00	0 -

Thanks for catching that typo in the data.

> There is a typo in the Mexico part of the northamerica file:
> # Shanks reports a transition at 1032-03-30 23:00, not 1932-04-01. I
> suppose the first date should be added 900 years ...

Thanks for catching that typo too.  I'll fix them both.