[skip ci] couple small corrections

before: failed with undefined index PHP error
now: fail with proper error complaining about missing argument.

[skip ci] Fixed typo

Fix typos in configurations guide

[skip ci] Fixed typos in properties guide

[ci skip] Update tutorial-mailing.md

[skip ci] Remove stability=dev

Shouldn't stability=dev be removed?

ensure syntax highlighting

Revert "Update output-data-widgets.md"

Update output-data-widgets.md

changed  $query->from(['author' => 'users'])  to  $query->from(['author' , 'users']) on line 354

close #5527

Possible typo.

close #5526

Add images to pt-BR guide [skip ci]

pt-BR guide/getting started/looking ahead [skip ci]

pt-BR working with databases guide [skip ci]

[skip ci] (typo) code missing bracket

Grammar fix [skip ci]

Create russian translation for caching-fragment.md

[ci skip] Create Russian translation of Caching Http Guide

spanish translate responses and some fixes [skip ci]

[skip ci] Italian translation of intro-upgrade-from-v1.md