Add read the docs projects

[ergo]

It would be great to have an example documentation project on RTD that illustrates how to work with the library.

[stevepiercy]

Demos could be hosted on the sponsored Linode that hosts docs, webob.org, pylonsproject.org, and trypyramid.com. Several core contributors have access, including me, @mmerickel, @bertjwregeer, @blaflamme.

Deployment should be automated and must be documented.