RhodeCode CE/EE

There's a PR that implements github flavored markdown extension which allows to create more elements like tables/lists.

It seems most of the items renders correctly, however some (like tables) are missing styles completly.

Here's how it looks on github: https://github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet

source file: https://github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet.md

we should copy that file content and make it look similar in our renderer