[skip ci] add a new CHANGELOG section for the next release cycle

Author: asomers

CHANGELOG.md

@@ -3,6 +3,12 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
+## [Unreleased] - ReleaseDate
+### Added
+### Changed
+### Fixed
+### Removed
+
 ## [0.6.0] - 5 December 2019
 ### Added