README: Fix docker-compose mention

Previously rendered poorly on both GitHub and Docker Hub.

Author: kylemanna

README.md

@@ -40,7 +40,7 @@ a corresponding [Digital Ocean Community Tutorial](http://bit.ly/1AGUZkq).
 
         docker run -v $OVPN_DATA:/etc/openvpn --rm kylemanna/openvpn ovpn_getclient CLIENTNAME > CLIENTNAME.ovpn
 
-## `docker-compose`
+## Docker Compose
 
 If you prefer to use `docker-compose` please refer to the [documentation](docs/docker-compose.md).