Add LaTeX support

[DomiDre]

I would love to also use some simple LaTeX within my markdown texts (to include some formulas in a post for example). I saw #68 but that got closed... and I found the package ngx-markdown-katex ( https://www.npmjs.com/package/ngx-markdown-katex ) which however is missing some features from ngx-markdown...

So... is there some specific reasons to avoid including katex optionally?

[jfcere]

Hi @DomiDre, thanks for your PR!

There is not specific reason not to include katex... I just never add the time to look deeper in its integration but I am glad you did it.

I will merge your PR but I will need to make some changes before to release it and fix failing tests.

This should be release during the week.

[jfcere]

Katex support is now live 🎉
Thanks again for you contribution @DomiDre!

• Update ngx-markdown to v8.2.0 to get the feature.
• Consult README.md file for installation instructions.
• Refer to the demo for an example @ https://jfcere.github.io/ngx-markdown/#katex