Built-in offline help manual

I don't want to open the browser to browse this repository for documentation. I want to keep it self-contained and able to be used offline.

Based on the commits in eepp, I guess ecode can render both markdown and html. This is like a piece of cake for you to add imo.

[SpartanJ]

Yes, this should be provided now that it's possible. I'll take a look on how to package it.