title: ThingsBoard GPIO Control widget status update
body: <p>I am building an IoT project using ThingsBoard platform. (using MQTT protocol)</p>
  <p>Using the GPIO control widget I am able to control the on/off relays of the remotely located sensors. But, I would like to get a frequent update regarding the state of the control relay switches.</p>
  <p>Can I somehow generate a &quot;getGPIOStatus&quot; on the sensor end (python on raspberry pi), and frequently transmit the status of the relay switches to ThingsBoard?</p>