squid-stats.conf is a configuration file for squid-stats?. It is a bit messy because it's contents is fed directly into grep and hence the need to escape the \'s and the .'s. The format is
ipmatch usernname
where ipmatch is a string that grep will match to the ip for the user
10\\.1\\.1\\. user1 10\\.1\\.2\\. user2 10\\.1\\.3\\. user3
No page links to squid-stats.conf.