Update CHANGELOG

Author: timoschinkel

CHANGELOG.md

@@ -1,5 +1,20 @@
 # Change Log
 
+## [2.0.0] - 2019-02-02
+
+### Added
+
+- Support for HTTPlug 2.0 and PSR-18
+
+### Changed
+
+- `\Http\Adapter\Guzzle5\Tests\ExceptionTest` extends `\PHPUnit\Framework\TestCase` instead of `PHPUnit_Framework_TestCase`
+
+### Removed
+
+- Support for PHP <7.0
+- Support for PHPUnit <6.0
+
 ## 1.0.1 - 2017-07-11
 
 ### Fixed