title: Json.Net adding $id to EF objects despite setting PreserveReferencesHandling to "None"
body: <p>I've already looked at <a href="https://stackoverflow.com/questions/11542144/how-to-remove-id-during-json-serialization">how to remove $id during JSON serialization</a> but the answers given do not seem to be working for me and I hope someone can figure out what I am doing wrong.</p>
  
  <p>Here is my code:</p>
  
  <pre><code>return JsonConvert.SerializeObject(target, new JsonSerializerSettings {
      NullValueHandling = NullValueHandling.Include,
      PreserveReferencesHandling = PreserveReferencesHandling.None,
      ContractResolver = new CustomContractResolver(),
      Converters = CustomConverters
  });
  </code></pre>
  
  <p>The output from this is still coming out with $id's, BUT, only on Entity Framework objects, is this by design?  If so, is there any way to prevent those $id's on Entity Framework objects?</p>