fix #29: --server is not optional

README.md

@@ -40,8 +40,7 @@ These commands are shown using the **testing server**.
 
 Want to use the **live server**?
 
-1. remove the `--server https://acme-staging.api.letsencrypt.org/directory`
-2. or change it to `--server https://acme-v01.api.letsencrypt.org/directory`
+1. change server to `--server https://acme-v01.api.letsencrypt.org/directory`
 
 **Note**: This has really only been tested with single domains so if
 multiple domains doesn't work for you, file a bug.