This avoids nasty surprises on upgrade if a site is using httpauth,
or passwordauth with an account_creation_password, and relying on
only a select group of users being able to edit the site. We can revisit
this for ikiwiki 4.
This was needed due to emailauth, but I've also wrapped all IP address
exposure in cloak(), although the function doesn't yet cloak IP addresses.
(One IP address I didn't cloak is the one that appears on the password
reset email template. That is expected to be the user's own IP address,
so ok to show it to them.)
Thanks to smcv for the pointer to
http://xmlns.com/foaf/spec/#term_mbox_sha1sum
Simon McVittie
Joey Hess