Create a documentation website

[travishathaway]

What is the idea?

We need a documentation website for the project to explain how this plugin works.

What should happen?

Copy over the documentation website used by https://github.com/conda/conda-libmamba-solver

The first page should be an introduction to the project including how to use it (e.g. how to configure auth handlers; how to use the login/logout commands).

Initially, there won't be much, but it should be able to grow if necessary.