OAS 3.0: Model names not displayed in operations

[hkosova]

Version: ft/oas3 branch
Spec: https://openapi-converter.herokuapp.com/api/v1/convert?url=http://petstore.swagger.io/v2/swagger.yaml

In 3.0 specs, the "Model" tab in operations does not display the model names.

[shockey]

Fixed!