Throw errors from sp for failed inserts

[adizaimi]

Throw errors on db:insert() failures in lua/sp.c:

1. from prepare, ex. wrong column name
2. from executing insert, ex. bad data conversion
3. from emitting error out of range -- fetch correct error

Signed-off-by: Adi Zaimi [email protected]

[akshatsikarwar]

This needs to be on an option and disabled by legacy_tunables

[akshatsikarwar]

This needs to be on an option and disabled by legacy_tunables

Should also test how this behaves when an insert fails in the context of a trigger, where handling the return code is the desired behavior. See: https://github.com/bloomberg/comdb2/blame/master/docs/pages/programming/triggers.md#L100