Initiate an authenticator registration.

Initiate an authenticator registration for IBM Verify instances or custom mobile authenticators that are built from the IBM Verify SDK.
A QR Code image is returned which can be scanned by IBM Verify, or custom mobile authenticators. The content of the QR Code will be used to complete the registration.

Entitlements:
- manageAuthenticatorsAnyUser (Manage authenticator registrations for all users)
- manageAuthenticators (Manage authenticator registrations for yourself)