Update README and CHANGELOG files

Author: martignoni

CHANGELOG.md

@@ -3,6 +3,10 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](https://semver.org/) and follow principles of [keep a changelog](https://keepachangelog.com).
 
+## Version 2.2.0, 2019-06-10
+### Added
+- Raspberry Pi 4B and other models are now supported (#70).
+
 ## Version 2.1.0, 2019-05-29
 ### Added
 - Manager can now use restart and shutdown buttons in the footer (#68).

README.md

@@ -12,7 +12,7 @@ This plugin enables a Moodle administrator to monitor some hardware settings, to
 
 Administrators and users with manager role can moreover restart and shutdown the MoodleBox with buttons in the footer of each Moodle page.
 
-The plugin is compatible with Moodle 3.6 or later. A Raspberry Pi model 3B or 3B+ is recommended.
+The plugin is compatible with Moodle 3.6 or later. A Raspberry Pi model 3B, 3B+ or 4B is recommended.
 
 ## Installation