Add syntax highlighting for docker-compose.yml

Home.md

@@ -8,9 +8,10 @@
 
 Adapt this file with your FQDN. Install [docker-compose](https://docs.docker.com/compose/) in the version `1.6` or higher.
 
-    version: '2'
+```yaml	
+version: '2'
 
-    services:
+services:
   mail:
     image: tvial/docker-mailserver:latest
     # build: .
@@ -26,9 +27,10 @@ Adapt this file with your FQDN. Install [docker-compose](https://docs.docker.com
       - maildata:/var/mail
       - ./config/:/tmp/docker-mailserver/
 
-    volumes:
+volumes:
   maildata:
     driver: local
+```
 
 #### Create your mail accounts