README bug

[knipknap]

The README explains how to use the router as follows:

from rest_framework_bulk.routes import BulkRouter

class UserViewSet(BulkModelViewSet):
    model = User

    def allow_bulk_destroy(self, qs, filtered):
        """Don't forget to fine-grain this method"""

router = BulkRouter()
router.register(r'users', UserViewSet)

However, BulkModelViewSet is not imported, neither is it defined in the example.

Similarly, the example registers UserViewSet, while the example above defines FooView - IMO it would be helpful if the example stayed in context.