mod_smacks: Fix some bugs with smacks-ack-delayed event triggering. The old code had several flaws which are addressed here. First of all this fixes the if statement guarding the event generation There where some timing glitches addressed by this commit as well.

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);