recalculating only the new hanchans shoud do the trick now.

the racalc cronjob reports erronous partly recalculations now.
A lot of code cleanups

src/content/views.py

@@ -31,7 +31,7 @@ class WYSIWYGEditorMixin(PermissionRequiredMixin):
             request, *args, **kwargs)
 
 
-class ArticleArchiveMixin():
+class ArticleArchiveMixin(object):
     """Mixin to add common context data to Views of the news archive."""
     category = None