Docker enhancements

[aprokop]

• Check the error code for create_container in docker-run.py. If it is not successful do not continue executing
• Add an option to postpone tearing down the container if something goes wrong so one could login into it and investigate
• Add an option to commit the container at the end of successful execution of docker-run
• Allow usage of local docker images

[dalg24]

The documentation for the Docker API client in Python is available here. create_container returns a dictionary with a 'Warnings' key. We may want to check that container.get('Warnings') is None.

[aprokop]

Updated checklist for using local docker images