Backporting TRUNK-3851 - Modules should be able to define message codes outside of their module's namespace
TRUNK-3867: getPatientIdentifiers(String identifier, List<PatientIdentifierType> patientIdentifierTypes, List<Location> locations, List<Patient> patients, Boolean isPreferred) does not restrict by location
backport to 1.9.x
TRUNK-3851 - removing some commented code
Missing Validators for relationship_type - TRUNK-3814

made some changes