mod_groups_internal: allow force-emitting group member addition events This is useful when a new plugin was loaded which handles that event to add some value. Then the command can be called (**not** from the plugin but from an upcoming admin shell module) to synchronise things.

module:hook("authentication-success", function (event)
	local session = event.session;
	local sasl_handler = session.sasl_handler;
	session.log("info", "Authenticated with %s", sasl_handler and sasl_handler.selected or "legacy auth");
end);