Remove gogoproto in favor of the standard protobuf compiler. This
removes any nonstandard extensions that were part of gogoproto such as
the custom types.
Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>
Trivially created by looking for every reference to .Variant and adding
OSVersion and OSFeatures, except the ones related to the string
representation of a Platform instance.
I then went through and ensured every assignment of OSFeatures that
might leak out, i.e., not local-only or for marhsalling purposes, uses
the append-to-nil idiom to avoid sharing the slice storage and allowing
accidental mutation after-the-fact.
Signed-off-by: Paul "TBBle" Hampson <Paul.Hampson@Pobox.com>