mod_http_oauth2: Create proper template for OOB code delivery This also improves security by reusing the security and cache headers, where mod_http_errors/http-message doesn't add such headers. Colors selected by taking rotating the error colors, rrggbb -> ggbbrr

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);