Finalize README

[jared321]

Much of the current content in the README should go to the User and Developer Guides. Once that is done, simplify the README and consider adding in standard content such as badges.

[jared321]

The landing page of the sphinx docs and the README of the Python package should be a proper subset of this file. In particular, they should not include the badges since those are tied to the state of the main branch in the repo at the present, rather than being frozen at the time that the sphinx docs and package were built.