Implements model save options, issue #110
Use admin2_url, redirect create form to index view.

Uses the template tag admin2_url to create namespaced view names
from inside of views.

Create model form now redirects to the model index page, as
django.contrib.admin. does.

Removed get_success_url from ModelListView, as generic.ListView
does not call this method.
Merge branch 'feature/save-options' of git://github.com/chrislawlor/django-admin2 into chrislawlor-feature/save-options