Update README.md

README.md

@@ -20,7 +20,7 @@ To see command-line options, run `docker run --rm wernight/ngrok --help`.
 
 Supposing you've an Apache or Nginx Docker container named `web_service_container` listening on port 80:
 
-    $ docker run --rm -it --link web_service_container wernight/ngrok ngrok http web_service_container:80
+    $ docker run --rm -it --link web_service_container wernight/ngrok ngrok http web_service_container:80 -log stdout
 
 
 ### Environment variables