Fixed changelog format

According to: https://keepachangelog.com

Author: AnonymousX86

docs/CHANGELOG.md

@@ -1,40 +1,53 @@
-This file contains changes made to `Python Password` program.
-
-## Pre-Alpha
+# Changelog
 
-### 0.2.2 - 16 May, 2020
+This file contains changes made to `Python Password` program.
 
-- Added tips for new users.
+## [0.2.2] - 2020-05-16
+### Added
+- Tips for new users.
 - Checking master passwords on program start.
-- Fixed bug: unable to save beta password with random password.
-- Fixed bug: "that password already exists" dialog showed up when alpha password wasn't set.
+### Fixed
+- Bug #1: Unable to save beta password with random password.
+- Bug #2: "That password already exists." dialog showed up when alpha password wasn't set.
 
-### 0.2.1 - 15 May, 2020
-
-- Updated GUI to material design standard.
+## [0.2.1] - 2020-05-15
+### Added
 - All functions of `v0.1.*` included.
+### Changed
+- Updated GUI to material design standard.
 
-### 0.2.0 - 10 May, 2020
-
-- First GUI pre-release.
-- Most functions from console UI version.
+## [0.2.0] - 2020-05-10
+First GUI pre-release.
+### Added
+- Most functions from `v0.1.*`.
+### Changed
 - User files are now saved to `AppData\Local` directory.
 
-### 0.1.2 - 4 May, 2020
-
+## [0.1.2] - 2020-05-4
+### Added
 - Cosmetic changes.
 - Checking files' integrity even more often.
-- Most od exceptions are handled properly.
-
-### 0.1.1 - 3 May, 2020
+### Fixed
+- Exceptions are handled properly.
 
-- Bugfixes, typos and idiot proofing.
+## [0.1.1] - 2020-05-3
+### Added
+- Idiot proofing.
 - Checking files' integrity more often.
-- More confirmations are needed.
-
-### 0.1.0 - 2 May, 2020
-
-- First usable pre-release.
-- Added functions:
-  - setting password,
-  - getting password.
+- More confirmations.
+### Fixed
+- Small bugs.
+- Typos.
+
+## [0.1.0] - 2020-05-2
+First usable pre-release.
+### Added
+- Set password option.
+- Get password option.
+
+[0.2.2]: https://github.com/AnonymousX86/Python-Password/releases/tag/v0.1-alpha
+[0.2.1]: https://github.com/AnonymousX86/Python-Password/releases/tag/v0.2.1-alpha
+[0.2.0]: https://github.com/AnonymousX86/Python-Password/releases/tag/v0.2.0-alpha
+[0.1.2]: https://github.com/AnonymousX86/Python-Password/releases/tag/v0.1.2-alpha
+[0.1.1]: https://github.com/AnonymousX86/Python-Password/releases/tag/v0.1.1-alpha
+[0.1.0]: https://github.com/AnonymousX86/Python-Password/releases/tag/v0.1-alpha