Deploy application with nginx and application_python

Not to be too picky, but we really should start using the ``nginx_app`` definition we have in ``osl-nginx`` to standardize on config templating. Unfortunately I don't know the status of that definition compared to all the work did in ``osl-apache`` to improve its features. In theory it shouldn't take very long to clean it up, but I'd feel much better if we used that.

@jordane thoughts on this?