HPCC-8842 Improve error message for code that would fail

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Step towards fixing module inheritance

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Another stepping stone... update comments

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Getting closer

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Initial partial version

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>