Fix broken User link name (it was possible to change link name to one that was already used, validation was not working correctly).
Patch by: Pawel Solyga
# Directions for web crawlers.
# See http://www.robotstxt.org/wc/norobots.html.
User-agent: HTTrack
User-agent: puf
User-agent: MSIECrawler
User-agent: Nutch
Disallow: /