Zabbix

A.F.I..PST [ZBXNEXT-5088] added active check availability status retrieval

Merge in ZBX/zabbix from feature/ZBXNEXT-5088-6.1 to master

* commit '6a16ab974a9901e6baa22793e8d5cd2b299b0857': (50 commits)
  .......... [ZBXNEXT-5088] removed unused variable
  .......... [ZBXNEXT-5088] added better comments in configs
  A......... [ZBXNEXT-5088] added actie_available to extend output
  .......... [ZBXNEXT-5088] upgraded to latest master
  ........S. [ZBXNEXT-5088] fixed incorrect calculation for active avail internal check
  .........T [ZBXNEXT-5088] fixed templates
  .......... [ZBXNEXT-5088] fixed config
  ........S. [ZBXNEXT-5088] added validation to accept only host active availability data from proxy monitoring this host
  ........S. [ZBXNEXT-5088] don't process active agent heartbeat messages on server if host is monitored by proxy
  ........S. [ZBXNEXT-5088] removed debug leftovers
  ........S. [ZBXNEXT-5088] refactored
  ........S. [ZBXNEXT-5088] refactored host avail data json building on proxy
  ........S. [ZBXNEXT-5088] host discovery - insert rtdata without ipc request
  ........S. [ZBXNEXT-5088] coding style fix, decreased unavailable proxy check to 10 minutes
  .......... [ZBXNEXT-5088] fixed database upgrade patch
  ........S. [ZBXNEXT-5088] simplified host availability resetting code in availability manager
  .......PS. [ZBXNEXT-5088] removed debug leftover
  .......PS. [ZBXNEXT-5088] various fixes
  .......PS. [ZBXNEXT-5088] various fixes
  ...G...... [ZBXNEXT-5088] fixed logging in agent
  ...