documentation

Pull request #2919: Feature/ZBX-26561 7.3 D

Merge in WEB/documentation from feature/ZBX-26561-7.3-D to release/7.4

* commit 'a309889be487ce217542a29338a1a2ac4b0006a3':
  ZBX-26561 formatting.
  ZBX-26561 list adjustment, added a link.
  ZBX-26561 added links.
  ZBX-26561 clarified information about omission of the host name.