Fixes #5001: `yii\rest\CreateAction`, `yii\rest\UpdateAction` and `yii\rest\DeleteAction` should throw 500 error if the model operation returns false without validation errors

ensure it is one of the input values

fixes #4880

Fixes #4424: Added `inline` and `mimeType` options to all file downloading methods provided in `yii\web\Response`

- If exception is internal it's always returned as HTTP 500 general purpose one.
- Type isn't exposed anymore.

Refactored `yii\web\User`.

fixes #4514