podman-create and -run have many options in common. To date,
these are copy-pasted and haphazardly maintained.
Solution: add an include mechanism, '@@option foo', such
that multiple md source files can fetch from one common file.
This is a Phase One commit, a very small subset of what's
possible. Purpose of this commit is ease of review. If this
passes review, much more (trickier stuff) will be forthcoming.
Signed-off-by: Ed Santiago <santiago@redhat.com>