title: v5.5 Elasticsearch Custom Serializer
body: <p>Is it possible in NEST / Elasticsearch-net 5.5 to make a custom serializer to only work on my own app's defined types and let the built in serializer handle the rest of Elastic packages own types?</p>
  
  <p>I would like to accomplish this because my custom serializer is failing to serialize Elasticsearch NEST queries to json string.</p>