documentation

Pull request #413: [ZBX-19382] Upgrading changes for 3rd party tools - 6.0

Merge in WEB/documentation from feature/ZBX-19382-6.0-D to release/6.0

* commit 'caefb3abc7fcb7112c1ca946f05a953bcd18e508':
  ZBX-19382 Edited block IDs in Upgrade procedure.
  ZBX-19382 Edited Upgrade procedure page.
  ZBX-19382 Edited Upgrade procedure page.
  ZBX-19382 Edited and formatted Upgrade and Whatsne
  ZBX-19382 Updated Whatsnew and Upgrade page.