Our FileConfig may not be consistent with the docker config

[kitchoi]

Referring to http://docker-py.readthedocs.io/en/latest/tls/

If one wants to use TLS but with self-signed certificate, docker tls should be set to True but tls_verify set to False. Whilst in our FileConfig, we would settlsto False and tls_verify to True (and then we assumed a CA file provide in the cert path so we verify against ourselves.)