Add datatype property for certifications and licenses

[marijane]

Both healthcare providers and clinics should be in the domain of this property

• [ ] Find example data to guide model implementation

[marijane]

nCertifications is an existing field in the Person table in the Profiles app.

[marijane]

After studying the MSOW data, this may need more detail. Or key-value modeling to indicate the various types of licenses and certifications.