browser side (contact list): Contact list improvments: - removed optional arguments from getContactBox: they are now managed by the hosting panel, as the arguments should be same for all contacts in a panel - contact name is no more specified on ContactBox creation, is gotten by the ContactLabel itself using the cache (TODO: "nick" listener) - renamed setMessageXXX to setAlert for consitency with QuickFrontend (furthermore the alert could be used for something else than waiting messages) - ContactBoxes are stored using bare jid - parent is used in ContactBox instead of host