The checkpoint manager provides a way to save the memory manager
`MemoryTable` both under the memory and under the state file.
Saving the `MemoryTable` under the state file can be useful when kubelet
restarted and you want to restore memory allocations for running containers.
Also, it provides a way to monitor memory allocations done by the memory manager,
and in the future, the state file content can be exposed under the pod metrics.
Signed-off-by: Artyom Lukianov <alukiano@redhat.com>
