Added new helper module for timelines. This helps to determine wether a given event or period has begun/isactive/ended. Patch by: Lennard de Rijk Reviewed by: to-be-reviewed

# 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: /