Feature: Add MQTT Topic monitor

[aikitori]

Hi!

A MQTT monitor would be awesome ;)

Maybe use some kinde of regex like the http monitor for evaluating?

Paho seems the one to go: https://pypi.org/project/paho-mqtt/ https://eclipse.dev/paho/ Github repo: https://github.com/eclipse-paho/paho.mqtt.python

Here a a list of other python clients: https://www.emqx.com/en/blog/comparision-of-python-mqtt-client