Zabbix

...G...... [ZBXNEXT-712] added new item vfs.dir.get[] for Agent and Agent2

Merge in ZBX/zabbix from feature/ZBXNEXT-712-5.5 to master

* commit '5b6d233e73aa9e403a3829ba16af5ecbb056cdd7':
  ...G...... [ZBXNEXT-712] reverted mutex
  ...G...... [ZBXNEXT-712] fixed path
  ...G...... [ZBXNEXT-712] fixed warning in PR and integration tests
  ...G...... [ZBXNEXT-712] fixed trailing spaces
  ...G...... [ZBXNEXT-712] fixed integration tests for Jenkins
  ...G...... [ZBXNEXT-712] fixed integration tests
  ...G...... [ZBXNEXT-712] fixed integration tests and crash
  ...G...... [ZBXNEXT-712] fixed issue with unknown user and added forgotten changes for Agent2
  ...G...... [ZBXNEXT-712] fixed some warnings in PR
  ...G...... [ZBXNEXT-712] removed trailing spaces in integration tests
  ...G...... [ZBXNEXT-712] added integration tests
  ...G...... [ZBXNEXT-712] fixed Agent2 compilation for Windows
  ...G...... [ZBXNEXT-712] added new item vfs.dir.get[] for Agent