[web server] #1642893 issue a 403 instead of a 500 on Unauthorized exception
To do so, we allow an arbitrary code to be passed to ``error_handler``. Default
error code is still 500.
.. -*- coding: utf-8 -*-
Server Architecture
-------------------
.. image:: images/server-class-diagram.png
`Diagramme ArgoUML`_
[FIXME]
Make a downloadable source of zargo file.
.. _`Diagramme ArgoUML`: cubicweb.zargo