code: public Object readResponse(Type returnType, InputStream input) throws Throwable {
  		return readResponse(returnType, input, null);
  	}
docs: Reads a JSON-PRC response from the server.  This blocks until
  a response is received.
  
  @param returnType the expected return type
  @param input      the {@link InputStream} to read from
  @return the object returned by the JSON-RPC response
  @throws Throwable on error