Auto-publish CEPs on conda.org

[jezdez]

Description

Since CEPs are an important part for evolving conda community standards, I wonder if it would make sense to have a first class section under conda.org/ceps to render them fully automatically during build time?

Tasks

• Find out how we can fetch CEP files from the conda/ceps repo
• Render a landing page under conda.org/ceps with a list of CEPs
• Show the CEPs in the left sidebar for easier selection

[jezdez]

Fixed in #220 and #222. /cc @jaimergp