Register patient with coded attributes

When registering a patient, it's common to collect secondary data about the patient. Most of OpenMRS's defaults are handled by the current 3.x registration app and many other fields can be captured as patient attributes. However, currently the handling for patient attributes only supports patient attributes that store user-entered strings. Often it is a requirement to capture coded data about the patient. Some examples:

• Occupation (or occupation type)
• Religion
• Country of origin / birth
• Civil status

We need a mechanism to support these coded patient attributes.

Ideally, we could extend the schema to support something like, e.g.,

{
  "fieldDefinitions": {
    "civilStatus": {
       "label": "Civil Status",
       "uuid": "123456-123-515-1231351",
       "type": "coded",
       "code": <some concept identifier>
     }
  }
}

This would create a drop-down field which allows the user to select the civil status from amongst those provided as concept answers to the given concept.