Consider capturing additional Staff Credential data in Ed-Fi Data Standard

Both Michigan and Tennessee have added a license number.

Additionally, Michigan extended Credential as its own entity (StaffREPCredential), including the standard Credential fields but also these additional fields:

• ProfessionalCertificateOrLicenseNumber - The number issued by the credentialing/licensing agency.
• REPTypeOfCredential - To indicate the REP type of credential held by the staff member as required by the REP assignment code. (Implemented as a Descriptor)
• StaffReference

Then, in StaffEducationOrganizationAssignmentAssociation, a StaffREPCredentialReferenceType was added to associate a credential with the assignment to which the credential applies.

For additional details, see linked issue DATASTD-940.