Merge changes from topic "biometric-strength"

* changes:
  Enforce that registered authenticators are not null
  Ensure that cancelling authentication ends up in the correct state
  Enforce authenticator registration
  Enforce that only public authenticator combinations are accepted
  Add phenotype namespace and flag for biometrics
  Use @Authenticators.Types for authenticator selection
  Add setAllowedAuthenticators(int) to BiometricPrompt