Enable usage of containers outside of Kubernetes

Kubernetes currently creates FOO_SERVICE_HOST and FOO_SERVICE_PORT env
vars as part of starting the containers. However this is not done when
starting them with plain docker.

Defaulting variables to their common version if they're not already set
allows the usage of --link in plain 'docker run' to wire together
containers.

Co-Authored-By: Charles Crouch <ccrouch@redhat.com>
Change-Id: I91098ff987b18646d901ac63a3a644fbb68fc857
Merge "Enable usage of containers outside of Kubernetes"