Add a CHANGELOG

[umoqnier]

Is your feature request related to a problem? Please describe.
A changelog can be useful for historic proposes because logs notable changes in the code in a human readable format

Describe the solution you'd like
Create a CHANGELOG.md file in the root of the repo and log notable changes

Additional context
To get a consisten changelog file is necesary to get a tags version system. I recommend the next schema: MAYOR.MINIOR.HOTFIX

Example:

• 0.0.1: First commit
• 0.0.2: Fixing a bug: Broke the admin UI when upload incorrect format texts
• 0.1.0: Change some code: A better way to get texts, changing colors and styles, deleting innecesary code
• 1.0.0: Adding a new feature: Delete rows in a document

A complete style guide for the changelog can be found here: https://keepachangelog.com/en/1.0.0/