http://idk.i2p/javadoc-i2p/com/thetransactioncompany/jsonrpc2/JSONRPC2Message.html
Throws: JSONRPC2ParseException - With detailed message if parsing
failed. appendNonStdAttribute public void appendNonStdAttribute ( String name, Object value) Appends a non-standard attribute to this JSON-RPC 2.0 message. This is
done by adding a new member (key / value pair) to the top level JSON
object representing the message. You may use this method to add meta and debugging attributes,
such as the request processing time, to a...