mod_python example configuration fixes

mod_python example configuration fixes

These fixes correct the example patchwork.mod_python.conf file to
actually work properly:

* Patchwork base directory needs to be in PythonPath so that
  things like "apps.urls" will import

* Set DJANGO_SETTINGS_MODULE to "settings" instead of
  "patchwork.settings" so that it can find the settings file to
  import

* Use LocationMatch instead of Location in order for the pattern
  matching to work (this was causing none of the images/stylesheets
  to be found when using mod_python)

Signed-off-by: Nate Case <ncase@xes-inc.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>