HPCC-12155 Add --help option

Signed-off-by: rpastrana <rodrigo.pastrana@lexisnexis.com>
Merge pull request #6430 from rpastrana/HPCC-12155-various-DESDL-issues

HPCC-12155 Add --help option

Reviewed-By: Russ Whitehead <william.whitehead@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>