Improve the web documentation

[Rami-Sabbagh]

Is your feature request related to a problem? Please describe.
The current documentation of LIKO-12 suffers from many problems, including:

• Generated on the user's browser, and so it's not indexable by search engines.
• It's hard to navigate between pages.
• The theme is not much good.

Describe the solution you'd like
We want a better documentation software, which:

• Stores the documentation in markdown format in a github repository.
• Generates static html pages, and so could use Travis for the generation.
• Has a search bar, to search throw the documentation.
• Makes it clear on how to contribute to the documentation.

Describe alternatives you've considered
I've been told about Docusaurus

Additional context
We've already tried:

• ReadTheDocs: Navigation problems with the mkdocs backend.
• MediaWiki on MiraHaze: Importing documentation generated from the .json files is not possible.
• Docsify: Not static html, hard to navigate.