Mark changes as releases 1.1.0

- Update CHANGELOG with PHP 8 support
- Mark changes as version 1.1.0

Author: timoschinkel

CHANGELOG.md

@@ -4,7 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## [1.1.0] - 2020-11-26
+### Added
+- Support for PHP 8
+
 ### Changed
 - Updated README with link to Packagist