Hide any inserted transformer from the user by returning the "true" DataSink from getDataSink.  The also fixes it changing the DataSink after a previous DataSink required multiple transformers.
Hide any inserted transformer from the user by returning the "true" DataSink from getDataSink.  The also fixes it changing the DataSink after a previous DataSink required multiple transformers.

etomica/etomica,ajschult/etomica,ajschult/etomica,etomica/etomica,ajschult/etomica,etomica/etomica