add template changelog for copying

Author: runxel

tpl/CHANGELOG.md

@@ -0,0 +1,21 @@
+# Changelog
+All notable changes to this object will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project has heard of [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+
+## Compatibility
+Archicad version XX
+
+## [Unreleased]
+
+## [1.1] – 20YY-MM-DD
+### Fixed
+- ....
+
+### Added
+- .....
+
+## [1.0] – 20YY-MM-DD
+First version of this object published.