cvs2cl enhancement for logging tag dates

Attached is a small enhancement to have a different view of tags, to have the
tags logged with the date the tag first (last in time) occured.

The patch adds the following command line option:

  -T, --tagdates Show tags in output on their first occurance

This allows for easy tracking of what changes occured before / after a
certain tag was made. A lot more understandable than to have the tag listed
on each file separately..

Example:

2002-04-25 16:31 flavio

        * templates/html/pptpconn.html: fixed reload of parent window on
        pptpconn.html

2002-03-27 22:15 tag V2_4

2002-03-27 22:15 henrik

        * templates/firewall: Fixup local firewalling for multilink

Regards
Henrik Nordström
MARA Systems AB