Add periodic task to remove stale shared uploads.

mayan/apps/common/literals.py

@@ -2,8 +2,11 @@ from __future__ import unicode_literals
 
 from django.utils.translation import ugettext_lazy as _
 
+
+DELETE_STALE_UPLOADS_INTERVAL = 60 * 10  # 10 minutes
 TIME_DELTA_UNIT_CHOICES = (
     ('days', _('Days')),
     ('hours', _('Hours')),
     ('minutes', _('Minutes')),
 )
+UPLOAD_EXPIRATION_INTERVAL = 60 * 60 * 24 * 7  # 7 days