documentation

Pull request #2035: feature/ZBXNEXT-8246-6.4-D-API. documented missing "max_repetitions" property.

Merge in WEB/documentation from feature/ZBXNEXT-8246-6.4-D-API to release/6.4

* commit 'f40963b611e621c22a5ea523eb58489e45195791':
  [ZBXNEXT-8246] documented missing "max_repetitions" property