New tz code and data

The files ftp://elsie.nci.nih.gov/pub/tzcode1999h.tar.gz and ftp://elsie.nci.nih.gov/pub/tzdata1999i.tar.gz are now available, incorporating the changes circulated on the time zone mailing list last week and earlier this week (modulo a small awk/nawk change in the Makefile). --ado