Investigate other markdown parsers

[twodayslate]

The current implementation is homemade.

https://github.com/shaps80/MarkdownText

iOS now supports markdown natively. Perhaps we can use this? I believe we can override the open url environment variable to control how to open the links.

[twodayslate]

Currently MarkdownText doesn't have interactive links so it isn't useful.

[twodayslate]

Parse stuff is HTML so idk if this is even helpful except for the user's about section.