Restructure to get the ArchiveStore off the ACB and allow it to be accessed by it id.  The aim is to ensure that the ACB is just a set of perishable information and doesn't contain objects that can't be persisted.  Since we aren't sure how we get the definition back, ie. it might not be a DAO in some models (ie. Orion) then we will need to let the OMR take care of this.