`$config` can now be a closure that will have the `$configInstance` passed as the first param.

updated docs.

close #4656

Fixes #4122: `Html::error()` and `Html::errorSummary()` are now accepting `encode` option. If set to false it prevents encoding of error messages

Fixes #4371: Active form client validation wasn't working in case of two models having same named fields

When rendering multiple models in the same ActiveForm if any of the field names in the two models is the same then the corresponding attribute in the yiiActiveForm object in yiiActiveForm.js (ie $('form').data('yiiActiveForm').attributes) of the first rendered model is overwritten by the attribute of the last model causing the client-side validation for the overwritten field not to run at all. Example: given two models Car and Owner with attributes {make, age} and {name, age} then if the Car is rendered first its age attribute will not have any client validation.

Docs guide russian translation: translated rest-routing.md into Russian

Fixes #4644: Added `\yii\db\Schema::createColumnSchema()` to be able to customize column schema used

Translated docs/guide/rest-controllers.md into Russian

Provide aggregate test runner

Update db-active-record.md to correct a minor typo

changed problem to problems to correct a minor typo.

Smarty improvements

Fixes #4659: adjusted nginx config in docs to serve 404 instead of "no input file specified" when accessing non-existing PHP file

Fixed typo in comments for generatePasswordHash

[skip ci] Translate docs/guide-ru/start-gii.md to russian language

[Uk][Guide] Add page translation

Grammar fixes