Feature: Add podman support

[jerdog]

While Docker is the de facto option for containers, it's not the only one. Adding podman as an option would be ideal, and broaden the potential audience.

[SvenDowideit]

podman won't be hard to support - and I imagine that lima (for OSX) would be similar, tho i've not used it in a looooong time. IIRC, unless you're doing something really interesting, the exec differences are likely to be just strings (and the pain of building a test harness)