config()
    function used to create new config entries in $globals.
    usually, a module need to create a ....Config class to store the defaults.

menu()
    function used to add entries to $globals->menu    

subscribe($forlife, $uid, $promo, $pass)
    triggered when a user subscription is sucessfull

prefs()
    function used to add boxes in htdocs/preferences.php
    must return a dictionnary : url, title, text, weight.