As discussed when podman has come up previously I don't think we should continue making unique image loading commands, instead we should:

• support podman + docker + tarball in a single kind load image
• for each image argument, we should:
  • check for a file first if it looks like a path / check if the file exists
  • check docker
  • check podman

For checking docker vs podman, we can potentially enhance it to cache if docker or podman are even in PATH and skip the ones that aren't installed.

We could also perhaps match the node provider in preferring these, but a couple things to consider:

• what about once we support another provider that may not have the ability to export images?
• what about predictable consistency across hosts?

I think it may be worth sticking to the simplest: a fixed order of these, and ensuring this is fast.
If a script/user really want to load from a particular source, they can always do like podman save hello-world:2 | kind load image -

EDIT: once we agree on the high level approach, I have a few more specific points to add about implementing this correctly.

cc @aojea @amwat @bostrt