fixed listen arg position

server.go

@@ -123,8 +123,12 @@ func HandleWebhook(w http.ResponseWriter, req *http.Request, webhookToken string
 
 func main() {
 	filename := "zuliprc"
+	listen := "localhost:8080"
 	if len(os.Args) > 1 {
 		filename = os.Args[1]
+		if len(os.Args) > 2 {
+			listen = os.Args[2]
+		}
 	}
 	cfg, err := loadConfig(filename)
 	if err != nil {
@@ -140,11 +144,6 @@ func main() {
 	}
 	zlbot.Init()
 
-	listen := "localhost:8080"
-	if len(os.Args) > 1 {
-		listen = os.Args[1]
-	}
-
 	http.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) { HandleWebhook(w, req, cfg.GitLabWebhookToken, &zlbot) })
 	log.Fatal(http.ListenAndServe(listen, nil))
 }