HPCC-10617 Add support for Cassandra

Added support for SET parameters and dataset fields

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
I don't think there's any such thing as a record with no fields in ECL. Which is why I decided not to reference it in the error message. I could have output separate error messages for the two cases, but decided it was overkill.