Control data model in test object for RSP evaluation tests

[gbicann]

Currently the test subject uses the general.registryDataModel input parameter to indicate whether they support a full data set or only a minimal data set.

For Main RSP evaluation, it would be preferable for this to be controlled by ICANN as a fixed parameter of the test object, not something that the test subject can specify.

This will require a change to both the test specs and the API spec.

See also: icann/rst-test-specs#147