documentation

Pull request #3964: feature/ZBXNEXT-10076-7.5-D

Merge in WEB/documentation from feature/ZBXNEXT-10076-7.5-D to release/8.0

* commit '659267ae9e4bfff7b729a2d00fe19d039e0a745e':
  [ZBXNEXT-10076] clarified part of MaxHousekeeper parameter description
  [ZBXNEXT-10076] fixed typos; restored part of MaxHousekeeperDelete parameter description
  [ZBXNEXT-10076] fixed shortcomings; optimized content
  [ZBXNEXT-10076] fixed shortcomings; optimized content
  [ZBXNEXT-10076] fixed shortcomings
  [ZBXNEXT-10076] fixed shortcomings
  [ZBXNEXT-10076] optimized housekeeping