Documentation: adoption of docsify for documentation pages

[allysonsouza]

Since our just-the-hm-docs is not being updated in a while and it's not compiling with the latest Ruby/Jekyll, I thought about this as an opportunity to adopt a third-party, easy to setup and updated solution, it's when I've found docsify, which seems to work really nice.

This way we could get rid of wiki, concentrating documentation on the same repository as code.

[roborourke]

Not come across this before. Do we publish docsify via GitHub pages? Is there an action or something we can use for that?

Also rather than duplicating the README.md, GitHub will look in docs/ for a readme if there isn't one in the root directory.

[allysonsouza]

I guess it's statically built locally and served trough /docs dir, so we should just point the repository settings to a branch and this directory.

[roborourke]

Which repository settings are you referring to?

[allysonsouza]

I based my answer from this article section:
https://judy.hashnode.dev/how-to-build-a-documentation-site-with-docsify-and-github-pages#heading-deploying-your-site-with-github-pages

[goldenapples]

We discussed updating or replacing this pull request to use just-the-hm-docs instead of docsify for consistency with other projects. However, the documentation updates in this branch (to the "Testing SSO Locally" page) should be preserved.

[roborourke]

@goldenapples if it's unlikely just-the-hm-docs will be updated any time soon I think for the sake of pragmatism just having readmes available is fine.