Clean up docker containers and images

docker-cleanup.sh

# Docker
function docker-cleanup {
  # Find all containers that have exited
  containers=`docker ps -a -q -f status=exited | xargs`
  if [[ $containers ]]; then
    # Remove exited containers
    docker rm $containers
  else
    echo "No containers to remove"
  fi

  # Find all images that are not tagged
  images=`docker images -a -q -f dangling=true | xargs`
  if [[ $images ]]; then
    # Remove untagged images
    docker rmi $images
  else
    echo "No images to remove"
  fi

  # List containers and images that remain
  docker ps -a
  docker images -a
}