title: CosmosDB DocumentClient.CreateDocumentQuery returns incorrect result for ISO formatted date string
body: <p>I have a CosmosDB collection where I am storing ISO formatted dates as strings, for example, I have saved a document with a <code>start</code> value of <code>2018-07-26T09:00:00Z</code> and when I look in the <code>Data Explorer</code> I can see the value saved correctly.</p>
  
  <p>I am using <code>Cosmonaut</code> to access my CosmosDB which exposes the <code>DocumentClient</code> and I am using <code>CreateDocumentQuery</code> to access my document but when the document gets returned from CosmosDB the <code>start</code> value is converted to a DateTime string <code>07/26/2018 09:00:00</code></p>
  
  <pre><code>var collectionUri = UriFactory.CreateDocumentCollectionUri("assessment-center", "ac-template-timetables");
  Document document = await _cosmonautClient.DocumentClient.CreateDocumentQuery(collectionUri, new SqlQuerySpec
  {
      QueryText = "SELECT * FROM c WHERE c.id = '713d5115-83cb-4005-abaa-25756ebc86d1'"
  }, new FeedOptions { EnableCrossPartitionQuery = true }).FirstOrDefaultAsync();
  </code></pre>
  
  <p>The above is my query, has anyone else encountered this and if so how did they resolve this problem, my expectation is that my string value should be returned as is and not interpreted as a <code>DateTime</code> which seems to be what is happening</p>