sysutils/podman: new port

podman (Pod Manager) is a fully featured container engine that is a simple
daemonless tool. podman provides a Docker-CLI comparable command line
that eases the transition from other container engines and allows the
management of pods, containers and images. Simply put: alias docker=podman.

podman uses Buildah(1) internally to create container images. Both tools
share image (not container) storage, hence each can use or manipulate
images (but not containers) created by the other.

PR: 267184
Reviewed by: arrowd
Reviewed by: dch
Sponsored by: SkunkWerks, GmbH
Differential Revision: https://reviews.freebsd.org/D37324