oneOf Schema Violations: name contained properties and elements that failed validation

[tedepstein]

This is another way to improve the validation error message for oneOf schema validations: #60 contains an example of a Swagger spec with a oneOf schema violation, and also includes the returned Error Report object. Within the hierarchy, there are some nested report objects whose instance is a property within the root context. For example:

                  {
                    "level": "error",
                    "schema": {
                      "loadingURI": "http://swagger.io/v2/schema.json#",
                      "pointer": "/definitions/headerParameterSubSchema/properties/in"
                    },
                    "instance": {
                      "pointer": "/paths/~1taxFilings~1{id}/put/parameters/0/in"
                    },
                    "domain": "validation",
                    "keyword": "enum",
                    "message": "instance value (\"body\") not found in enum (possible values: [\"header\"])",
                    "value": "body",
                    "enum": [
                      "header"
                    ]
                  }

I assume the same thing can happen when nested array elements fail validation.

In these cases, our error message should identify the contained object that failed the validation.