- adds REST API CA external id field
- adds rest api for external fields
- refactors authentication interfaces for federation
- alters authentication moduels to return AuthResult interfaces
- allows AuthResults to provide external x509 certs as session certs
- deletes ottca enrollment when CA is deleted
- adds API tests
- adds migration to remove currently orphaned ottca enrollments
- migration tested on a v15 database with orphaned ottca enrollments