Reworked the CFAcc 2.0 model to specify the DelDeps and PopDeps.

Working on this model has me thinking I may have to switch wholesale
to DelDep specifications, because in order to delete an account you
need to be able to delete all the references to it, which means that
during a Tenant deletion it needs to obey the sub-element deletion
rules for an Account, whereas currently that wouldn't happen and
it would fail to delete the Tenant.