Add a TopClientTransactionListener that manages event raising.
Raise all events from that listener rather than individually from different places in re-store.
Remove IDataManagementCommand.Begin/End methods - these should be empty now anyway.
TBD: Event scoping? Some notification methods are raised within a CTx scope, some are not.
(Separate task?) CEPReplaceSameCommand should not derive from REPModificationCommand (it's not a modification).