Communication over proxy not supported

Compared to the Client object from paho.mqtt.client , the TBDeviceMqttClient object does not support the function **proxy_set** to set a proxy server.

Workaround is:
tb_client = TBDeviceMqttClient(...)
tb_client.**_client**.proxy_set(proxy_type=socks.HTTP, proxy_addr="...", proxy_port=...)

Could you please provide this feature in the right way.

Thanks