The ready/valid Signals were missing from the DDS Reader and Writer Interfaces,
preventing the user from effectively using non-Type dependent operations
(like GET_OFFERED_DEADLINE_MISSED_STATUS).
The L1_Type1_test1 was extended to test for this non-type dependent operation.
Since the Type Specific user facing entities did not actually wrap the
DDS entities, but connected to them through port signals, a more
semantically correct name would be "interface", since they are the user
facing interface of the DDS entities.
