Patched error handling problems in Transmitter implmentations. In particular: 1) Ensured that libdap::Error objects are converted to BESDapError objects when caught. and 2) Catch and rethrow BESError objects whenever they could be thrown so they don't get swept up as unidentified errors in a catch(...) clause.
Patched error handling problems in Transmitter implmentations. In particular: 1) Ensured that libdap::Error objects are converted to BESDapError objects when caught. and 2) Catch and rethrow BESError objects whenever they could be thrown so they don't get swept up as unidentified errors in a catch(...) clause.

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