Map machines to pods

[chris-sanders]

I'm trying to get information on machines and have found that I can't find a way via libmaas to determine which Pod a machine is on or even which Machines are on a given Pod. I've tried walking machines to look for a Pod reference as well as walking Pods to see if I could list the machines on them.

I don't see a way to get this information from either side, and it should probably be present on both. A Pod should be able to track which machines are on it and a machine should know which pod it's on.