Added changelogs for new versions (#248)

* Added changelogs for new versions

* Added changelog for adapter-common

* Added more changelogs

Author: Nyholm

Changelog.md

@@ -2,12 +2,21 @@
 
 The change log describes what is "Added", "Removed", "Changed" or "Fixed" between each release.
 
+## 3.1.0
+
+### Added
+
+* Support for PHP 8
+
+### Fixed
+
+* Return result from `Doctrine::clear()`
 
 ## 3.0.1
 
 ### Changed
 
-* Bumped versions on dependencies. 
+* Bumped versions on dependencies.
 
 ## 3.0.0