documentation

Pull request #1947: feature/ZBXNEXT-9237-7.2-D. improved Browser items documentation.

Merge in WEB/documentation from feature/ZBXNEXT-9237-7.2-D to release/7.2

* commit '062db01f941c0a6a151047979069f3d2715b5f32':
  [ZBXNEXT-9237] added performance-related recommendation
  [ZBXNEXT-9237] added "Initialize browser with GUI" example
  [ZBXNEXT-9237] moved "Initialize browser" example
  [ZBXNEXT-9237] refined "Take screenshots" example
  [ZBXNEXT-9237] added "Take screenshots" example
  [ZBXNEXT-9237] added missing browser.setScreenSize() method
  [ZBXNEXT-9237] moved "Initialize browser" example
  [ZBXNEXT-9237] removed unnecessary backticks
  [ZBXNEXT-9237] refined "Find links" example
  [ZBXNEXT-9237] added "Find links" example
  [ZBXNEXT-9237] added "Monitor websites with Browser items" quick reference guide
  [ZBXNEXT-9237] moved ChromeDriver note
  [ZBXNEXT-9237] updated example to show use of parameters