Add change log

Signed-off-by: Mathias L. Baumann <[email protected]>

Author: Marenz

RELEASE_NOTES.md

@@ -1,5 +1,11 @@
 # Frequenz Python SDK Release Notes
 
+## Enhancements
+
+* Many tasks, senders and receivers now have proper names for easier debugging.
+* The resample log was improved to show more details.
+* The `Sample` class now has a nice `__str__` representation.
+
 ## Bug Fixes
 
 * Fix bug with `LoggingConfigUpdater` not updating root logger level.