title: What's the correct format for empty GUIDs for JSON.NET to be deserialized?
body: <p>What's the correct format for empty GUIDs to be sent to the server using JSON.NET for deserialization?</p>
  
  <p><code>"{"id":"","name":"Test"}"</code> results in <code>"Unrecognized Guid format."</code></p>
  
  <p><code>"{"id":null,"name":"Test"}"</code> results in <code>"Value cannot be null."</code></p>
  
  <p><code>"{"id":"00000000-0000-0000-0000-000000000000","name":"Test"}"</code> works, but I don't want to force clients to provide this.</p>