Refactor Required and Permitted Subattributes

Required subattributes apply to Name and Address, and can be configured on a per-enrollment flow basis or via CO Settings (which does not affect enrollment flows).

Permitted subattributes apply to Name only, and can only be set via CO Settings (which DOES affect enrollment flows).

Unify this design, possibly into a common configuration based on RequiredEnum. Note in some cases the per-enrollment flow based configuration may be desirable, to (eg) collect a given name only as a preferred name, while other name fields collect given/middle/family.