Complement THEO with an MQTT broker

[kKdH]

We plan to use MQTT for data exchange purposes between DuTs and peers on the one hand and CARL and other services on the other hand. Examples are:

• Current and voltage measuring and analyses
• Control of Actors.
• Read/Write signals

Because of this, THEO should be extended to provide an MQTT broker integrated into the current setup.

• [ ] Select an appropriate MQTT Broker which matches our requirements. - encryption - authentication - container image - cloud ready
• [ ] Integrate the selected Broker into THEO

Should be done after: #59

[kKdH]

Before we start to integrate MQTT into openDuT we should consider kuksa.val as data and signal hub. #59

[eet1mu3]

rumqtt could be a possible contender. I have it working as a demo in standalone mode, but could be also integrated.