Create "About" Copy

We need a short paragraph of "about" text that introduces Code for Cary/America and the Dev Map application. It can either be formatted in HTML or plain text, and I can pull it into the site, OR it could be added directly to the about box text, see:

https://github.com/CodeForCary/django-dev-map/blob/master/permit_map/static/permit_map/templates/about.html
