django/django — pull request #452 by crodjer (2012-10-20 13:38:20+00:00)
Title: Sessions cleanup logic in backend

Cleanup logic now lies in the backend. It should be executed based on the currently set backend.
Also Adds a cleanup functionality for the file and db backend.

Possibly related: [#18978](https://code.djangoproject.com/ticket/18978)
Not exactly a fix for the ticket (My change sets pre date the issue).