Create an API to handle the upload and management of subunit data

The current RefStack API allows for the upload, management, and verification
of test results by server administrators. These capabilities, though
sufficient for the current scope of RefStack, will need an API expansion in
order to allow for similar data management of subunit data results. This
expansion will enable those organizations looking to achieve a greater degree
of interoperability to securely share the details of test runs with the
Foundation so as to get assistance with getting their OpenStack instance to
successfully meet interop standards.