title: Error setting keen.timestamp, value of property keen must be an object, is newtonsoft.json.linq.jproperty
body: <p>I'm using the Keen.IO .NET sdk and I can't seem to override the keen.timestamp property.  I keep receiving the error:</p>
  
  <pre><code>value of property keen must be an object, is newtonsoft.json.linq.jproperty"}
  </code></pre>
  
  <p>If I remove the keen property, then the event saves fine, but the keen.timestamp throws an error, if added.   The KeenClient.AddEvent() seems to check for a JObject but I'm not sure why JProperty is being found.  Any ideas?  Thanks in advance!</p>
  
  <p>Here's my test code:</p>
  
  <pre><code> var aEvent = new
      {
      keen = new[] { new { timestamp = "2000-05-30T12:12:12Z" } },
      username = user,
      position = i,
      event_id = "A123",
      score = new Random().Next(1, 11),
      demographics = new[] { new {gender = "M", city = "San Francisco", state = "CA"}}
      };
      keenClient.AddEvent("events_test", aEvent);
  </code></pre>