add changelog

Author: aaraney

CHANGELOG.md

@@ -0,0 +1,10 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+## [Unreleased]
+
+## [0.3] - 2022-09-11
+### Fixed
+- display error message when layer fails to load (#3).
+- bring widget to focus if already on screen and try to launch with icon.
+- layer is not added if icon button is pressed repeatedly.