Adding oath specs

I pulled out all HTTP authorization and instead implemented both Github omniauth and octokit to authenticate based on whether the person is a member of the correct github organization and team. If they are not a member of the correct organization or the correct team, a user session is not created and they are not signed in. If they are not signed in, they are not allowed access to the admin controllers.

Once authenticated, a session[:type] is set, allowing the helper methods is_admin? and signed_in? to be used.