Implemented clean shutdown

src/app.py

@@ -89,7 +89,16 @@ def main() -> None:
         client.username_pw_set(config.MQTT_USERNAME, config.MQTT_PASSWORD)
 
     client.connect(config.MQTT_HOSTNAME, config.MQTT_PORT, 60)
-    client.loop_forever()
+
+    try:
+        client.loop_forever()  # This blocks
+    except KeyboardInterrupt:
+        logging.info("SIGINT recieved! Stopping...")
+        pass
+
+    client.disconnect()
+    loopingtimer.stop()
+    BirbnetesIoTPlatformStatusDriver.cleanup()
 
 
 if __name__ == "__main__":