How to add custom syntax

[alanlai1234]

Thank you for the amazing library!

I am trying to see if I can modify this library so that it can support custom markdown syntax, for example additional blockquote colors, like github's note, warning containers. I am aware of custom markup parser, but i couldn't figure out if I extend presentionIntent for additional blockquote style, how to let the library render that.

Thanks for any help!