Add CHANGELOG

CHANGELOG

@@ -0,0 +1,18 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+### Added
+### Changed
+### Deprecated
+### Removed
+### Fixed
+### Security
+
+## [1.0.0] - 2018-09-01
+### Added
+- Initial release. The date above is inaccurate; this first version was released sometime in the fall of 2018.
+- This release had a Django backend and a [Sigma.js](http://sigmajs.org/) graph.