This connects the new CRI ContainerCheckpoint RPC to the existing
internal checkpoint functions. With this commit it is possible
to checkpoint a container in Kubernetes using the Forensic Container
Checkpointing KEP (#2008):
# curl X POST "https://localhost:10250/checkpoint/namespace/podId/container"
Which will result in containerd creating a checkpoint in the location
specified by Kubernetes (usually /var/lib/kubelet/checkpoints).
This is a Linux only feature because CRIU only exists on Linux.
Rewritten with the help of Phil Estes.
Signed-off-by: Phil Estes <estesp@gmail.com>
Signed-off-by: Adrian Reber <areber@redhat.com>