Extensions were added twice
Updated changelog
Adds twig lexerOptions to ViewRendererTest to demonstrate error
Fixes Twig lexerOptions throwing exception (#3877) and adds test for lexerOptions
Sphinx Gii generator created
Docs about Sphinx Gii generator added
Updated twig extension changelog
Fixes #3968: Messages logged in shutdown functions are not handled
Fixes #3939: `\yii\Inflector::slug()` improvements:

- Added protected `\yii\Inflector::transliterate()` that could be replaced with custom translit implementation.
- Added proper tests for both intl-based slug and PHP fallback.
- Removed character maps for non-latin languages.
- Improved overall slug results.
- Added note about the fact that intl is required for non-latin languages to requirements checker.
Fixed changelog
Renamed `TwigSimpleFileLoader` into `FileLoader`
Fixed changelog wording
Translate docs(concept-components.md) to russian.
Corrected grammatical errors.
log fatal errors to yii logs.
Fixes #3280: Support dynamically attaching anonymous behaviors
Fixes #3535: Syntax changes

- Removed `form_begin`, `form_end`
- Added `use()` and `ViewRenderer::uses` that are importing classes and namespaces
- Added widget dynamic functions `*_begin`, `*_end`, `*_widget`, `widget_end`
- Added more tests
Fixes #3956: Flash messages set via `Yii::$app->session->setFlash()` will be removed only if they are accessed
Update a tip and an example

- add a tip that rbac.php is needed to create manually when using PhpManager.
- update that RbacController example needs to import Yii namespace.
Changed descriptive extension name to ID