Updated changelog (#54)

Nyholm · web-flow · commit d69210afc4ac · 2018-03-05T10:21:43.000+01:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -5,6 +5,7 @@
 - dropped support for PHPUnit < 7.0
 - [BC Break] add return type hints to all `toString()` methods of the constraint classes for compatability with PHPUnit 7
 - dropped support for PHP < 7.1
+- Allow for completely empty configuration
 
 ## 3.1.0 
 
