Use Keep A Changelog-esque format

CHANGELOG.md

@@ -1,12 +1,22 @@
-# Change Log
+# 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).
+
+Up until 0.9.3 this file was generated automatically by
+https://github.com/skywinder/Github-Changelog-Generator
 
 ## Unreleased
 
+### Fixed
+
 - fix incorrect keys bech32 HRP by always using the ones provided by the library
 
-## Release 0.13.0
+## [0.13.0](https://github.com/input-output-hk/jormungandr/releases/tag/v0.13.0) - 2021-09-24
 
-**New features:**
+### Added
 
 - Expiration block date must be set on all incoming fragments.
   Fragments in the mempool that are not included to a block prior to
@@ -15,7 +25,7 @@
   the expiration date can be ahead when accepted into the mempool.
 - Provide node metrics through the Prometheus API.
 
-**Changes:**
+### Changed
 
 - Only a single leader or stake pool is supported in the node configuration.
 - Change HRP for Bech32 keys used in the voting process to improve
@@ -25,15 +35,15 @@
   for backward compatibility.
 - Voting protocol elliptic curve backend is changed to Ristretto.
 
-**Bug fixes:**
+### Fixed
 
 - No reordering for the fragments submitted to the mempool in a batch via the
   REST API.
 - Writing of persistent fragment logs was slow, changed to use buffering.
 
-## Release 0.12.0
+## [0.12.0-rc.2](https://github.com/input-output-hk/jormungandr/releases/tag/v0.12.0-rc.2) - 2021-07-29
 
-**New features:**
+### Added
 
 - Persistent fragment logs, optionally enabled to record all fragments received
   by the node and accepted into the mempool. These logs can be used for
@@ -43,7 +53,7 @@
 - `scripts/bootstrap.py`, a cross-platform Python script to replace the older
   collection of outdated shell scripts.
 
-**Changes:**
+### Fixed
 
 - Updated the Poldercast implementation to use poldercast 1.2
   and reworked quarantine rules to improve network stability.
@@ -59,7 +69,7 @@
 - Added logging to track REST requests, including possible OpenZipkin/B3
   tracing information from the HTTP headers.
 
-**Bugs fixed:**
+### Fixed
 
 - Use voteplan ID as the CRS for private voting protocol to prevent use of
   compromised CRS values.
@@ -2190,7 +2200,3 @@ Rolled in recent fixes, testing improvements, and dependency updates for the Cat
 - new test case for genesis utxo stake pool [\#443](https://github.com/input-output-hk/jormungandr/pull/443)
 - improve jcli account-id parsing  [\#442](https://github.com/input-output-hk/jormungandr/pull/442)
 - remove stake key and related certificate, fix network compilation [\#440](https://github.com/input-output-hk/jormungandr/pull/440)
-
-
-
-\* *This Change Log was automatically generated by [github_changelog_generator](https://github.com/skywinder/Github-Changelog-Generator)*