Migrate ResearchStudy and ResearchSubject

[liberaliscomputing]

The current migration misses:

• ResearchStudy: https://github.com/ncpi-fhir/ncpi-model-forge/blob/master/site_root/input/resources/examples/ResearchStudy-example-research-study-id.json
• ResearchSubject: https://github.com/ncpi-fhir/ncpi-model-forge/blob/master/site_root/input/resources/examples/ResearchSubject-example-research-subject-id.json

Migrate these as instances.