MQTT: Implements reconnecting in publish thread in case thread is waken-up but client is disconnected.
Note: paho's lostConnection callback got already disabled in previous commit.
*.pyc
**/__pycache__
.vscode
**/build/**
*.class
**/.svghmithumbs/**
**/my_*.der
**/my_*.pem
tests/tools/Docker/requirements.txt
**/management.json
**/.secret
doc/_build/**
doc/locale/**
C_runtime/**/*.d
C_runtime/**/*.o