update changelog

Changelog.md

@@ -2,6 +2,13 @@
 
 All notable changes to this project will be documented in this file.
 
+## [0.15] - 2023-05-16
+- Added sentry SDK integration using SENTRY_DSN environment variable
+- Added NREN policy data
+- Changed layout of tables
+- Fixed colors in charging mechanism table
+- Refactor to use flask-sqlalchemy and flask-migrate
+
 ## [0.14] - 2023-05-03
 - Added a navigation sidebar to Organization pages