code: func containerReference(reference string) (name string) {
  	if parts := strings.Split(reference, ":"); len(parts) == 2 && (parts[0] == "container" || parts[0] == "service") {
  		// We'll just assume here that the reference is a name, and not an id, even
  		// though docker supports it, since we have no bullet-proof way to tell:
  		// heuristics to detect whether it's an id could bring false positives, and
  		// a lookup in the list of container names could bring false negatives
  		name = parts[1]
  	}
  	return
  }
docs: // If the reference follows the `container:foo` pattern, return "foo"; otherwise, return an empty string