For hierarchical machines it seems like it would be
quite useful to allow nested machines to initialize to
states that are not just none so to enable this allow for
providing a callback that will be used to determine the
callback for all nested machines (and nested-nested
machines) so that they can be initialized to the users
desire.
Change-Id: I45a0c0e0c2a976e0df094e6c728f943766be7c7a
151f447a8a