documentation

Pull request #2029: feature/ZBX-24980-7.2-D. clarified mention of double precision.

Merge in WEB/documentation from feature/ZBX-24980-7.2-D to release/7.2

* commit '3e46ad796bd34b89e0725ff351584ba90d1b9f69':
  [ZBX-24980] restored and clarified mention of double precision
  [ZBX-24980] removed mention of double precision