Is your feature request related to a problem? Please describe.
Continuation of #751.

Describe the solution you'd like
Reloader should be able to restart Rollouts that use spec.workloadRef (or, more specifically, Rollouts with null spec.template).

Describe alternatives you've considered
Migrating all Rollouts from using spec.workloadRef to using spec.template—which is impractical.

Additional context
I sketched a possible solution at the end of this comment, but it requires adding a kube.Clients member to the ContainersFunc interface.