support nydus commit operation

[imeoer]

For a running container with a nydus image, we can support container commit just like docker commit, the commit operation packs the container writable layer as a new image.

References:

cgroup freezer: https://www.kernel.org/doc/Documentation/cgroup-v1/freezer-subsystem.txt
nerdctl commit: https://github.com/containerd/nerdctl/blob/main/pkg/imgutil/commit/commit.go#L67

We can support it in nydusify commit or nerdctl commit.

[ywcYY]

Received, currently interpreting the commit part of the code

[imeoer]

@PerseidMeteor are working on https://github.com/nydusaccelerator/nydus-cli

[PerseidMeteor]

This issue can closed by #1543