title: Parsing error should be thrown for a Json Payload while validating it with a Json Schema, if 2 same property name exists?
body: <p>For e.g. if there is property called "Description" then if I validate a json payload against a json schema and put 2 times "Description", then it should throw an error.,as there are 2 fields with same key name.</p>
  
  <p>The Json Schema:</p>
  
  <pre><code>{
    "$schema": "http://json-schema.org/draft-04/schema#",
    "$id": "http://example.com/test1.schema.json",
    "title": "test1",
    "description": "Schema for test1",
    "additionalProperties": false,
      "definitions":{
  
          "link":
          {
          "type": "object",
          "additionalProperties": false,
          "required": 
              [
              "customer2"
              ],
           "properties":{
              "customer2":
              {
              "$ref": "#/definitions/customer"
              }
          }   
          },
  
          "customer":{
              "type": "object",
              "additionalProperties": false,
              "required": 
              [
              "Code",
              "Description",
              "OrderID"
              ],
              "properties":{
                  "Code": {
                "type": "number"
              },
              "Description": {
                "type": "string"
              },
              "OrderID": {
                "type": "string"
              }
              }   
          }
      },
      "type": "object",
      "properties": {
  
          "customer1":{
              "$ref": "#/definitions/link"
          },
  
          "chocolates": {
                    "type": "string"
  
  
          }
  
      }   
  
  
  }
  </code></pre>
  
  <p>The Json Payload:</p>
  
  <pre><code>{
      "customer1": {
          "customer2": {
              "Code": 0.1,
              "Description": "a",
                "Description": "a",
              "OrderID": "a"
          }
      },
      "chocolates": "a"
  }
  </code></pre>
  
  <p>The following Json payload gets validated against the Json schema, when I want it throw an error as there are 2 "Description" tags.</p>