Going forward, persist profiles encrypted to the CloudKit container.
Conversely, read from the encrypted field if any, falling back to the
plain JSON field.
WARNING: the change is NOT backward compatible, as it would defeat the
purpose. That is, once the profile is stored encrypted, the old plain
profile is erased and its content won't be readable by older versions of
the app.
* Make specific message levels a default extension
* Define Loggable protocol
* Keep track of message originator metadata
* Fix tracing of Core Data logs
* Log query on entity not found