added --volumes option to [docker-compose down] in up.sh so as not to leak docker volumes
added --volumes option to [docker-compose down] in up.sh so as not to leak docker volumes

cyber-dojo/runner_stateless,cyber-dojo/runner_stateless,cyber-dojo/runner,cyber-dojo/runner_stateless,cyber-dojo/runner_stateless,cyber-dojo/runner_stateless,cyber-dojo/runner_stateless,cyber-dojo/runner_stateless,cyber-dojo/runner