Enable image-lookup

[ignasi35]

This repo requires kustomize so we can adjust the image setting on the Deployment in the YAML files.

OpenShift offers a feature called image-lookup which coul dmake the above obsolete so we could reference image: "hello-lagom:1.0-SNAPSHOT" in all environments instead of requiring:

## in overlays/openshift/kustomization.yml
images:
  - name: "hello-lagom"
    newName: "docker-registry-default.centralpark.lightbend.com/lagom-scala-openshift-smoketests/hello-lagom"