Use getFromKeyFieldsOr404 in slots() and allocateSlots()
Handling of the exception is done by the view decorator.
Patch by: Sverre Rabbelier
# 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: /