* Support `checkpoint --pre-checkpoint`
* Support `checkpoint --with-previous`
* Disable `restore --import-previous` for the remote client since we had
to send two files which in turn would require to tar them up and hence
be a breaking change. Podman 4.0 would be the chance and I hope we'll
find time before that to remote-restore prettier.
Note that I did not run over swagger yet to check whether all parameters
are actually documented due to time constraints.
Fixes: #12334
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>