WSGI Handler for patchwork

[martin f. krafft]

I made patchwork work with WSGI, which is probably the preferred
method to let Apache2 and Django talk to each other. This required
a certain number of changes to the way patchwork handles namespaces:

1. django-registration should live in the global PYTHONPATH, not in
   the apps namespace.
2. Patchwork should refer to its own modules with the full path,
   e.g. apps.patchwork.urls instead of patchwork.urls.

The attached patches work for me. I hope they find their way into
Patchwork.