adding convenience helpers

[amnezzia]

No description provided.

[amnezzia]

needed for service scripts

[matt2000]

I can't remember, is there still an advantage to doing it this way rather than using boto3? And if there is, I wonder if we should keep it in python rather than shell'ing out? Looks like we could call awscli.clidriver.create_clidriver().main(['s3', 'more', 'args', 'go', 'here']) to do the same thing without relying on a subprocess.