[kronolith] Logout function for main menu

[Chuck Hagenbuch]

Quoting Martin List-Petersen <martin@list-petersen.dk>:

> Unfortunately i couldn't find any function to check if somebody is logged in
> or not, like available in IMP ( if (($reason = IMP::authenticate(null, true))
> !== true) ). This function the would make it possible to turn this menu off,
> if the user isn't logged in.

Auth::getAuth() - returns either a username or false.

-chuck

--
Charles Hagenbuch, <chuck@horde.org>
"What was and what may be, lie, like children whose faces we cannot see, in the
arms of silence. All we ever have is here, now." - Ursula K. Le Guin