Allow an internal pod template reference or object

Extracted from #1600, starts #170
Yeah, round trip should catch all of these things (although I'll double check that our initialization doesn't hide that).  We're not protected today from making a field round-trippable (adding it to the old api) but the fuzzer just nils it each time.  A negative round trip test should be done... but it's a lot of work.

----- Original Message -----
> >  				return err
> >  			}
> > +			out.CurrentState.Replicas = in.Status.Replicas
> 
> hm-- this is asking for a subtle bug if another field gets added to Status. I
> guess our fuzz test will catch it.
> 
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