Fix aligned equations in mkdocs docs

[alexe15]

The aligned environment is apparently not working by default with mkdocs but with vscode markdown. Fix via additional mkdocs plugins?

[timueh]

Mkdocs can use different plugins for markdowns. We can try to install this extension, and then register it via the yaml file for mkdocs.

[timueh]

Here is a list of third-party extensions for python-markdown, which is used by mkdocs. That should help!

[timueh]

Here's a concrete example of how to interface a third-party extension in mkdocs. Nice!

[alexe15]

It works now, the important thing is to put a blank line before and after your $$....

[alexe15]

Done, put a blank line before and after the $$...$$ block.