add link to letsencrypt-nginx-proxy-companion

Author: MichaelSp

README.md

@@ -125,6 +125,9 @@ $ docker run --volumes-from nginx \
 Finally, start your containers with `VIRTUAL_HOST` environment variables.
 
     $ docker run -e VIRTUAL_HOST=foo.bar.com  ...
+### SSL Support using letsencrypt
+
+[letsencrypt-nginx-proxy-companion](https://github.com/JrCs/docker-letsencrypt-nginx-proxy-companion)is a lightweight companion container for the nginx-proxy. It allow the creation/renewal of Let's Encrypt certificates automatically. 
 
 ### SSL Support