Fix port not being set with command flag

main.go

@@ -40,7 +40,7 @@ func setupSettings() error {
 }
 
 func main() {
-	flag.StringVar(&addr, "l", ":8089", "host:port of the MovieNight")
+	flag.StringVar(&addr, "l", "", "host:port of the MovieNight")
 	flag.StringVar(&sKey, "k", "", "Stream key, to protect your stream")
 	flag.Parse()
 
@@ -66,10 +66,14 @@ func main() {
 		os.Exit(1)
 	}
 
-	if addr != "" {
+	if addr == "" {
 		addr = settings.ListenAddress
 	}
 
+	if addr[0] != ':' {
+		addr = ":" + addr
+	}
+
 	// A stream key was passed on the command line.  Use it, but don't save
 	// it over the stream key in the settings.json file.
 	if sKey != "" {