Zabbix

.......PS. [DEV-2503] added database connection object with corresponding API and backwards layer for current database API

Merge in ZBX/zabbix from feature/DEV-2503-7.1 to master

* commit 'b0eb61010cd4b05deb033c0d16f218df6e93fc88': (26 commits)
  .......P.. [DEV-2503] fixed build warning with sqlite
  .......... [DEV-2503] fixed includes
  .......PS. [DEV-2503] changed type name
  .......PS. [DEV-2503] improved managed database connection handling
  .......PS. [DEV-2503] fixed logging of uninitialized variable
  .......PS. [DEV-2503] fixed slow query logging
  .......PS. [DEV-2503] updated postgresql 'read only recoverable' option handling
  .......PS. [DEV-2503] fixed db version handling
  .......PS. [DEV-2503] removed redundant includes
  .......PS. [DEV-2503] fixed includes
  .......... [DEV-2503] fixed cmocka warnings
  .......... [DEV-2503] fixed cmocka warnings
  .......... [DEV-2503] fixed warnings
  .......PS. [DEV-2503] fixed warnings
  .......PS. [DEV-2503] fixed build with postgresql
  .......PS. [DEV-2503] fixed warnings
  .......... [DEV-2503] updated __zbx_static/__zbx_attr_weak defines
  .......... [DEV-2503] fixed database mocks in tests
  .......PS. [DEV-2503] fixed dbconn usage
  .......... [DEV-2503] updated cmocka tests
  ...