HK-724, HYRAX-316, update the testsuite to reflect the empty constraint case.
HK-724, HYRAX-316, update the testsuite to reflect the empty constraint case.

OPENDAP/hdf5_handler,OPENDAP/hdf5_handler,OPENDAP/hdf5_handler,OPENDAP/hdf5_handler,OPENDAP/hdf5_handler,OPENDAP/hdf5_handler