Docker 1.10 does not guarantee that the pulled digest matches the digest
on disk when dealing with v1 schemas stored in a Docker registry. This
is the case for images like
centos/ruby-23-centos7@sha256:940584acbbfb0347272112d2eb95574625c0c60b4e2fdadb139de5859cf754bf
which as a result of #30366 cannot be pulled by Kube from a Docker 1.10
system.

Instead, use RepoDigests field as the primary match, validating the
digest, and then fall back to ID (also validating the match). Adds more
restrictive matching.