Add core View.make_progress() method

so callers no longer need to import `SessionProgress` and create directly

tailbone/views/purchasing/receiving.py

@@ -49,7 +49,6 @@ from webhelpers2.html import tags, HTML
 
 from tailbone import forms, grids
 from tailbone.views.purchasing import PurchasingBatchView
-from tailbone.progress import SessionProgress
 
 
 log = logging.getLogger(__name__)
@@ -1810,7 +1809,7 @@ class ReceivingBatchView(PurchasingBatchView):
         """
         batch = self.get_instance()
         key = '{}.receive_all'.format(self.get_grid_key())
-        progress = SessionProgress(self.request, key)
+        progress = self.make_progress(key)
         kwargs = {'progress': progress}
         thread = Thread(target=self.auto_receive_thread, args=(batch.uuid, self.request.user.uuid), kwargs=kwargs)
         thread.start()