mod_sasl2_bind2, mod_sasl2_sm: Remove bind2 <features/> wrapper element
This was dropped from the spec. It's more consistent with SASL2.
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);