Introduce a sysregistriesv2.V1RegistriesConf and V2RegistriesConf data types
Introduce a sysregistriesv2.V1RegistriesConf and V2RegistriesConf data types

This will make it easier to add more v2-specific top-level configuration
items in the future, and it allows users that need to represent a v1 configuration
to use a single type instead of hard-coding the top level of v1 configurations.

Does not change behavior.

Signed-off-by: Miloslav Trmač <9c008e38982a5397deb855345fb164f0558459ae@redhat.com>

containers/image,containers/image