Incorrect optionality of attributes

[mjcgm]

The optionality of the attributes is not considered correctly. E.g. in the generated Swagger file, the Patient.gender is said to be required although the conformance statement doesn't. We used

fhir-swagger --fhir_url http://test.fhir.org/r3 --conformance_path="/metadata?_format=application/json" --dstu3 --output r3.json

and got

    ...
    "Patient": {
      "description": "",
      "type": "object",
      "properties": {
        ...
        "gender": {
          "type": "string",
          "minLength": 1
        },
        ...
      },
      "required": [
        "resourceType",
        "id",
        "text",
        "identifier",
        "active",
        "name",
        "gender",
        "photo",
        "contact",
        "managingOrganization",
        "link"
      ]
    },
    ...