Let's not merge this until we merge things on the auth-server side, but to explain what's going on:
The first commit just moves everything into a subdirectory named "fxa-oauth-server". This is the commit that would be imported into the auth-server repo.
The second commit deletes it that subdirectory, and adds stub docs files to talk about what happened.
This prepares the fxa-oauth-server repo for being imported into fxa-auth-server; ref https://github.com/mozilla/fxa-auth-server/issues/2679