Zabbix

...G...... [ZBX-22399] added tls and default support to MQTT plugin for Zabbix agent 2

* commit 'e610944b1ef8d1e0a073cdf1633529672e7954e6':
  ...G...... [ZBX-22399] reverted removed parameter from MQTT plugin README
  ...G...... [ZBX-22399] cleaned up Zabbix agent 2mqtt plugin README
  ...G...... [ZBX-22399] updated README.md for mqtt plugin in Zabbix agent 2
  .......... [ZBX-22399] updated MQTT and MySQL Zabbix agent 2 readme files
  .......... [ZBX-22399] added change log
  ...G...... [ZBX-22399] added tls and default support to MQTT plugin for Zabbix agent 2

(cherry picked from commit aee11839019c2c7167412541d5a721be14598d69)