Documentation update: Docker example update (#96)

* Set traefik container version to 2.3 in docker-compose example. This supports recent lets encrypt changes.
* Remove docker swarm related references. Docker swarm example is no more valid. Docker compose is the best example available atm.

Readme.md

@@ -170,10 +170,11 @@ my.server.name {
 version: '2.2'
 networks:
   default:
+
 services:
   proxy:
     # The official v2 Traefik docker image
-    image: traefik:v2.2
+    image: traefik:v2.3
     hostname: proxy
     networks:
       - default
@@ -266,8 +267,6 @@ services:
 
 > Complete Guide available at: https://github.com/satishweb/docker-doh
 
-> No IPV6 Support: Docker Swarm does not support IPV6 as of yet. Issue is logged [here](https://github.com/moby/moby/issues/24379)
-
 > IPV6 Support for Docker Compose based configuration TBA
 
 ## DNSSEC