DOC: update CHANGELOG

CHANGELOG.md

@@ -15,6 +15,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * `get_property` method also accepts instances of properties now, e.g.
   `record.get_property(Property(name="length"))`
+* the value of properties is parsed to python types (int, float, boolean) when
+  setting the value with the setter and when the datatype changes. Before this
+  change, the value was parsed to python types only when parsing an xml and
+  only for int and float.
 
 ### Deprecated ###