[ci skip] Russian translation for tutorial-core-validators

[ci skip] controllers guide translated

[ci skip] [Uk][Guide] Add pages translation

 try using the new Docker setup of travis-ci

- do not allow boolean values for integer columns
- use native boolean type with boolean values
- removed workaround that turned out to be wrong when schema and values
  are used correctly. Workaround resulted from wrong usage of boolean
  values before.

fixes #4672

[ci skip] unneeded use Model

speed up process a lot because 3 composer updates are reduced to one

Revert "Fixes #4829: Removed `PARSING_ONLY` from `\yii\rest\UrlRule` to allow creating non-GET URLs for forms and tests"

This reverts commit 4ffbfec9.