[docs] add a note about label on services. remove unnecessary comment…

…s from examples.

README.md

@@ -117,6 +117,8 @@ Labels can be added to services to modify the behavior of *Gantry* for particula
 | `gantry.update.options=<string>`         | Override [`GANTRY_UPDATE_OPTIONS`](#to-add-options-to-services-update). |
 | `gantry.update.timeout_seconds=<number>` | Override [`GANTRY_UPDATE_TIMEOUT_SECONDS`](#to-add-options-to-services-update). |
 
+> NOTE: You must apply the labels to the services not the containers. If you are using docker compose files to setup your services, you need to add the label to the [deploy](https://docs.docker.com/reference/compose-file/deploy/#labels) section.
+
 ## FAQ
 
 [Authentication](docs/authentication.md)

examples/cronjob/docker-compose.yml

@@ -7,8 +7,6 @@ services:
       - /var/run/docker.sock:/var/run/docker.sock
     environment:
       - "GANTRY_NODE_NAME={{.Node.Hostname}}"
-      # The gantry service is able to find the name of itself service. Use GANTRY_SERVICES_SELF when you want to set a different value.
-      # - "GANTRY_SERVICES_SELF=${STACK}_gantry"
       - "GANTRY_SLEEP_SECONDS=0"
     deploy:
       replicas: 0