Zabbix

.......PS. [ZBX-20638] fixed handling of db version higher than supported

Merge in ZBX/zabbix from feature/ZBX-20638-6.1 to release/6.2

* commit '3ef9e8a31f6fcf5770edd9f8057ac6f0f353f037':
  .......PS. [ZBX-20638] refactoring
  .......PS. [ZBX-20638] fixed suggention to enable AllowUnsupported on server db < min_hard
  .......PS. [ZBX-20638] fixed conflict
  .......PS. [ZBX-20638] refactored
  .......P.. [ZBX-20638] fixed proxy start
  .......P.. [ZBX-20638] fixed proxy start
  .......P.. [ZBX-20638] fixed proxy startup with less than minimal db version
  ..F....... [ZBX-20638] fixed code style
  ..F....... [ZBX-20638] added fail-safe default in case an unknown flag is received from server; updated error messages
  ........S. [ZBX-20638] fixed code style
  .......PS. [ZBX-20638] fixed handling of db version higher than supported