documentation

Pull request #3355: feature/ZBXNEXT-9848-7.5-D: Host prototype modal window.

Merge in WEB/documentation from feature/ZBXNEXT-9848-7.5-D to release/8.0

* commit 'ad6e2580f51f7fb374ab8436ad0956d3cd53db8d':
  [ZBXNEXT-9848] Adjusted wording
  [ZBXNEXT-9848] Updated content
  [ZBXNEXT-9848] Updated screenshots