Zabbix

.......PS. [ZBXNEXT-7498] moved internal items processing from history to regular pollers

Merge in ZBX/zabbix from feature/ZBXNEXT-7498-6.1 to master

* commit 'ba5afe60f85d182e40af1499d7ebdab497a5e436':
  .......P.. [ZBXNEXT-7498] style fix
  .......P.. [ZBXNEXT-7498] style fix
  .......P.. [ZBXNEXT-7498] style fix
  .......P.. [ZBXNEXT-7498] style fix
  .......PS. [ZBXNEXT-7498] fixed maxid calculation after sending data to server
  .......PS. [ZBXNEXT-7498] minor fix
  .......PS. [ZBXNEXT-7498] reworked zabbix[proxy_history] approximate calculation
  .......PS. [ZBXNEXT-7498] code review rework2
  .......PS. [ZBXNEXT-7498] code review rework
  .......PS. [ZBXNEXT-7498] fixed tests
  .......PS. [ZBXNEXT-7498] fixed included headers
  .......PS. [ZBXNEXT-7498] moved internal items processing from history to regular pollers