[news] Yii Swagger 2.1

Version 2.1 of Yii Swagger package has been released. Here is the list of changes included in the new version:

• Added support for psr/http-message of versions ^2.0.
• Raised required yiisoft/yii-view version to ^7.1.
• Added \Yiisoft\Swagger\Action\SwaggerJson and \Yiisoft\Swagger\Action\SwaggerUi actions, mark \Yiisoft\Swagger\Middleware\SwaggerJson and \Yiisoft\Swagger\Middleware\SwaggerUi clases as deprecated (they will be removed in the next major version).
• Added support for swagger-api/swagger-ui of version 5.