bug everyone class not fully working

[da4throux]

Bug Description: if a module has only a class 'everyone' it never shows, even when a user is logged in

Analysis: in login_user only the modules with the current_user in their class are shown, The code specifies that modules with everyoneClass should not be turned off, but they were never turned on in the first place. I think the confusion came from login turning off the modules with a default class except the one that had everyone in it: as they should stay on. However it makes the assumption that all modules with an everyone class has also a default class, which might not be the case. Fix: re-write to add everyoneClass to the modules being turned on & off when user log in & out. I cannot see the harm of turning on / off twice a class, so that might happen though...