title: How can I ignore unknown enum values during json deserialization?
body: <p>How can I get Json.net not to throw up when my enum doesn't match string value provided in the json property?</p>
  
  <p>This happens when I create enum based on current documentation, but the third party API adds more enum values later.</p>
  
  <p>I would be happy with either marking special value as Unknown or using a nullable enum and unmatched value would return null.</p>