New lite-server implementation
    
    The new development server depends on werkzeug instead of paste. The
    werkzeug WSGI server comes with some additional features, most
    noticeable multi-processing server. The IPA framework is not compatible
    with threaded servers. Werkzeug can serve static files easily and has a
    fast auto-reloader.
    
    The new lite-server implementation depends on PR 314 (privilege
    separation). For Python 3 support, it additionally depends on PR 393.
    
    Signed-off-by: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Martin Basti <mbasti@redhat.com>