Add custom port variable for wordpress (#103)

* add variable for custom public port

* add public_port variable

templates/wordpress/0/docker-compose.yml

@@ -3,7 +3,7 @@ wordpress:
   links:
     - db:mysql
   ports:
-    - 80:80
+    - ${public_port}:80
 
 db:
   image: mariadb