[imp] patch for blacklist

[Chuck Hagenbuch]

Quoting Aide Florent <faide at alphacent.com>:

> I am really ok with the idea of having some Advanced users' options but I
> feel we could let an admin choose for a whole site if he wants it to be 
> the default behaviour. Just to make sure the first time a new user logs in
> the link is/is not available.

This is why admins can lock preferences.

-chuck

--
Charles Hagenbuch, <chuck at horde.org>
must ... find ... acorns ... *thud*