bug 1467532: Update to Django 1.11.16
bug 1467532: Update to Django 1.11.16

* Django 1.11.15 → 1.11.16: Fix race condition in update_or_create()

mozilla/kuma,a2sheppy/kuma,escattone/kuma,SphinxKnight/kuma,mozilla/kuma,jwhitlock/kuma,Elchi3/kuma,a2sheppy/kuma,jwhitlock/kuma,Elchi3/kuma,escattone/kuma,jwhitlock/kuma,SphinxKnight/kuma,SphinxKnight/kuma,SphinxKnight/kuma,Elchi3/kuma,Elchi3/kuma,SphinxKnight/kuma,jwhitlock/kuma,mozilla/kuma,a2sheppy/kuma,Elchi3/kuma,a2sheppy/kuma,escattone/kuma,jwhitlock/kuma,mozilla/kuma,a2sheppy/kuma,SphinxKnight/kuma,mozilla/kuma