Render preview Markdown

[ruslandoga]

Maybe preview could render the markdown, right now it's showing it "raw" https://staging.hexdocs.pm/?q=ecto:

> **Requirement**: This guide expects that you have gone through the [introductory guides](installation.html) and got a Phoenix application [up and running](up_and_running.html).

[josevalim]

Yes, we should render Markdown indeed. Although in this particular case, I would remove the block quote from the description. I will push it soon.

EDIT: pushed.