docs: update changelog

Cleanup changelog and update to match commit history with the exception of inital commits.

CHANGELOG.md

@@ -7,28 +7,48 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-## [1.2.0] - 2020-02-07
-### Added
-- CONTRIBUTING.md
+## [1.3.0] - 2020-03-20
+### Changed
+- Set Systemd timer (minecraft-stats.timer) from monotonic time to realtime.
+Default every 6 hours.
+
+## [1.2.1] - 2020-03-01
+### Changed
+- Remove redundant Systemd backup timer properties (minecraft-backup.timer).
+
+## [1.2.0] - 2020-02-22
+### Changed
+- Set Systemd backup timer (minecraft-backup.timer) from monotonic time to
+realtime and run every ten minutes.
+
+## [1.0.1] - 2020-02-08
 ### Changed
 - Correct step order, prompt and title (README.md).
+- Correct spelling error (README.md).
 - Correct clone URL (README.md).
 - Add Systemd hyperlink (README.md).
 - Add missing install steps for user and group (README.md).
+- Add two assumptions (README.md).
 
-## [1.0.0] - 2020-02-06
+## [1.0.0] - 2020-02-07
 ### Added
 - CHANGELOG.md
+- CONTRIBUTING.md
 - LICENSE
 - minecraft-paper.service
 - minecraft-spigot.service
-- minecraft-vanilla.service
-- README.md
-
+- minecraft-vanila.service
 ### Changed
-- Refactor clean up
-  - minecraft-backup.service
-  - minecraft-stats.service
+- Correct step order, prompt and title (README.md).
+- Systemd unit cleanup.
+- Correct description of Systemd unit (minecraft-stats.service).
+- Correct document formatting issues (README.md).
+- Add Git dependency (README.md).
+- Add hyper links (README.md).
+- Add steps for editing Systemd units (README.md).
+- Add example output (README.md).
+- Add LICENSE reference (README.md).
 
 ### Removed
-    - minecraft.service
+- Remove files not associated to the project.
+- Remove redundant Systemd unit minecraft.service.