* Update native.DefaultAuthor to get the name registered from the user's JWT
license in a way that avoids cyclic dependency errors.
* When plus_dpp.go#GetRegistration succeeds, it updates DefaultAuthor to the
registered name. The main.go now gets and prints the registered owner to
ensure this is populated on startup.
* Return correct ErrRegisteredFeature error when the FOSS version fails
to load embedded doodads.