* feat: verify the availability of PoP participants
* simplified and improved logging
* added MQTT-based availability check for PoP participants
* extended MQTT mocking
* Only the block proposer will send out the MQTT messages to the pop participants
* Added a configuration value for the MQTT response timeout
* removed parallel execution of one test case
* added r/w locking to the MQTT response processing
* set MQTT timeout unit to ms
Signed-off-by: Julian Strobl <jmastr@mailbox.org>
* added MQTT lib
* added MQTT config params: domain, port user, password
* sending PoPInit commands to devices par of the pop (after delivery of the PoPInit message)
* Added test case to verify the working of the MQTT connection (test is skipped and designed for manual tests (lack of credentials))
---------
Signed-off-by: Jürgen Eckel <juergen@riddleandcode.com>
