Upgrade to conduit v0.6.0; add credentials/environment to driver, mock_status as optional driver attributes

DRY up transaction-related parsers and make JSON creation more dynamic.

Add customer find/create actions.
Merge pull request #6 from conduit/ATOM-1669_host_override_and_mock_status

Upgrade to conduit v0.6.0; add credentials/environment to driver, mock_status