IoT Platform command processing not correctly handling json.

IotDevice.commands() returns the commands information as a JSON object.

With Iot Platform (IotfDevice) the key "payload" contains the complete MQTT message rather than extracting the command data (the "d" key in the MQTT message).

An IoT Platform message contains two keys, "d" and "ts".

• "d" is the data for the message
• "ts" is an optional ISO8601 timestamp

The intention was that the "payload" key be the payload of the command (not the message) for the json format to simplify code for others, and also not force every application to have to fetch the "d" key.