Merge pull request #2889 from ethereum/enhancement/changelog

Changelog to 1.x branch added

CHANGELOG.md

@@ -0,0 +1,39 @@
+# 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).
+
+<!-- EXAMPLE
+
+## [1.0.0]
+
+### Added
+
+- I've added feature XY (#1000)
+
+### Changed
+
+- I've cleaned up XY (#1000)
+
+### Deprecated
+
+- I've deprecated XY (#1000)
+
+### Removed
+
+- I've removed XY (#1000)
+
+### Fixed
+
+- I've fixed XY (#1000)
+
+### Security
+
+- I've improved the security in XY (#1000)
+
+-->
+
+## [Unreleased]
+
+## [1.0.0]