issue #746

Obsolete keys searching isn't work when we have serveral categories for tranlation with DbMessageSource. Obsolete array filled with last message category only, because it'll always overwritten.

Added `yii\console\Controller::EXIT_CODE_NORMAL` and `yii\console\Controller::EXIT_CODE_ERROR` constants, `yii\console\MigrateController` now returns `yii\console\Controller::EXIT_CODE_ERROR` in case of failed migration

`yii\console\controllers\AssetController::actionTemplate()` advanced to include `jsCompressor` and `cssCompressor` to the template.

Adjustments code according to the standards.
Adding missing PHPDoc comment.

issue #3026

issue #2852

adjust existing Console Controllers and docs

this term is resolveable by the php docs when linking types in apidoc