Upgrade the documentation system to git-based system

The project aims to migrate the FreeCAD documentation system to a file-based, versioned system based on Git and Markdown so that it supports multiple languages for users globally and allows switching between offline and online versions. The current system is at constant risk of losing data due to the MediaWiki software used to support it. The project involves community interaction to research solutions and then upgrade the entire system to new software. The completion of the project will result in a better documentation system for the FreeCAD software that is robust and supports version control. It will also allow the user to download, or pack, the entire FreeCAD documentation to be able to access it on a machine with no internet connection, which is the goal of switching from MediaWiki to a file-based solution.