added russian translation
translation fixes
small translation fixes
controllers guide translated
Merge pull request #4871 from Ragazzo/structure_controllers_docs_translated

[ci skip] controllers guide translated
Merge pull request #4869 from prosophist/feature

[ci skip] Russian translation for tutorial-core-validators
Fixes #4424: Added `inline` and `mimeType` options to all file downloading methods provided in `yii\web\Response`