Flood Recorder: Detect attempts to flood a site with many accesses

This class can detect when a site is being flooded with too many requests to pages served by PHP scripts.

It keeps track of the IP addresses of the computers of the users that access the site and stores in a file of a given directory the information about the last access.

It stores in that file time of the last access or blocking expire time if that IP was already blocked due to previously detected flood attempt.