Fold the StringDeserializer into ResponseDeserializer
As they overlapped
So we have four deserialization cases: content as Xml or Json, and data wrapped in a "response" or not
we don't support the case where there is Jon wrapped in a response
But we didn't before. This brings it closer
Merge pull request #173 from AnthonySteele/one-response-deserializer

Fold the StringDeserializer into ResponseDeserializer