Remove stale usergroups

The Koelner Linux und U.n.i.x Gruppe -> Investment website
FreeBSD Spain -> The usergroup stoped their activities 8 years ago
The Ames Free-Unix Group (amesfug) -> online bookie shop
The Raleigh BSD Users Group -> online bookie shop
Bay Area FreeBSD Users Group (BAFUG) -> online bookie shop
Windsor Unix Users Group -> It looks like a Chinese online store
FreeBSD Brazil Group (FGB) -> Domain on sale
User Group BsdSul -> Right now it's a personal website

Patch by: carlavilla@
Reviewed by: bcr@
Differential Revision: https://reviews.freebsd.org/D24299