How to make custom code renderers

[logicminds]

First off thank you for forking this project. Using this component is really easy and has replaced quill.

I want to make a custom code render function where when the user runs the specifies the following code block the javascript code will convert to a math function using something like https://latex.codecogs.com/ or katex to render on the client. Quilljs has a method of doing this called formula which is pretty simple to setup. If I can get this working I would be happy to make a PR. I am just not sure how to do this. How do I detect and render this math code block?

```math
\int \frac{1}{x} dx = \ln \left| x \right| + C
```