message: Prune old/unused docker images after jenkins run.
diff: @@ -85,3 +85,9 @@ elif [ -n "$IS_RELEASE_TAG" ]; then
  else
  echo "skipping image push. HEAD sha does not appear to be master, nor is it a release tag: $GIT_SHA_HEAD"
  fi
  +
  +echo "Cleaning up old Docker images..."
  +docker rm $(docker ps -a -q) || true # delete stopped containeres
  +docker rmi $(docker images -q) || true # delete images (fails on images currently used)
  +docker volume ls -qf dangling=true | xargs -r docker volume rm || true # delete orphaned volumes
  +echo "Done!"
  