Added documentation + bumped version to 8.1.0 for new feature

permission_handler/CHANGELOG.md

+## 8.1.0
+
+* Added support for iOS 12+ Critical Alerts permission requesting.
+* NOTE: This requires applying to Apple and recieving a special entitlement from them inorder to work. See [this article](https://medium.com/@shashidharyamsani/implementing-ios-critical-alerts-7d82b4bb5026) for an explination on how to use Critical Alerts. 
+
 ## 8.0.1
 
 * Updated API documentation for the `PermissionStatus.permanentlyDenied` status.

permission_handler/pubspec.yaml

 name: permission_handler
 description: Permission plugin for Flutter. This plugin provides a cross-platform (iOS, Android) API to request and check permissions.
-version: 8.0.1
+version: 8.1.0
 homepage: https://github.com/baseflowit/flutter-permission-handler
 
 flutter: