This also incorporates the version string into the package name so
that incompatibile versions will fail to connect.
Arbitrary choices:
- The proto3 package name is runtime.v1alpha2. The proto compiler
normally translates this to a go package of "runtime_v1alpha2", but
I renamed it to "v1alpha2" for consistency with existing packages.
- kubelet/apis/cri is used as "internalapi". I left it alone and put the
public "runtimeapi" in kubelet/apis/cri/runtime.
We let dockershim implement the kubelet's internal (CRI) API as an
intermediary step before transitioning fully to communicate using gRPC.
Now that kubelet has been communicating to the runtime over gRPC for
multiple releases, we can safely retire the extra interface in
dockershim.
Implement CRI stats for dockershim using docker stats. This enables use
of the summary api to get container metrics on Windows where CRI stats
are enabled.