southamerica timezone update for Brazilian Summer Time 2001

[Paul Eggert]

Thanks for the patch.  As it happens, I had already incorporated
<http://pcdsh01.on.br/figuras/HV3916.gif> into the draft patches that
I sent to tz at elsie.nci.nih.gov on Tuesday, but your patch gave me a
chance to double-check it.  I compared my changes with yours, and
found one disagreement: you changed America/Belem to adopt DST this
year, whereas I changed America/Fortaleza.  I checked the decree
again, and I think America/Fortaleza is the correct entry to modify.
So (unless I'm misreading the Portuguese, which is quite possible :-)
I think the Tuesday draft patches are OK.