HPCC-9096 Include "ecl packagemap validate" section into Roxie Ref

Signed-off-by: JamesDeFabia <James.Defabia@LexisNexis.com>
Merge pull request #4200 from JamesDeFabia/9096_include_ecl_packagemap_validate_RDDE_Ref

HPCC-9096 Include "ecl packagemap validate" section into Roxie Ref

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>