Zabbix

.......PS. [ZBX-16230] fixed unreachable host next check calculation uses both unreachable settings and flexible item interval

* commit 'f6b433e021df3029dd0691185db372fdfc3fba0a':
  .......PS. [ZBX-16230] corrected test case
  .D........ [ZBX-16230] edit ChangeLog
  .......PS. [ZBX-16230] add some testcases
  .......PS. [ZBX-16230] removed unused parameter, added test case
  .......PS. [ZBX-16230] minor code change with ITEM_STATE_NORMAL define
  .......PS. [ZBX-16230] use separate function for unreachable checks calculation
  .......PS. [ZBX-16230] revert changes
  .......PS. [ZBX-16230] revert changes
  .......PS. [ZBX-16230] fixed unreachable nextcheck for shorter update intervals
  .......PS. [ZBX-16230] fixed unreachable host behavior uses item update interval instead of settings for unreachable
  .......PS. [ZBX-16230] Revert fixed unreachable host behavior uses item update interval instead of settings for unreachable
  .......PS. [ZBX-16230] fixed unreachable host behavior uses item update interval instead of settings for unreachable

(cherry picked from commit d7e51f9d975a169592d5aad690b06598b4413b17)
(cherry picked from commit c98d7e7518c82f36f1fd46423c1bd3c66ce405ed)