bug 1401246: Update DDT injection for MIDDLEWARE
bug 1401246: Update DDT injection for MIDDLEWARE

Update the code that enables Django Debug Toolbar (DDT) for the change
from MIDDLEWARE_CLASSES to MIDDLEWARE in Django 1.10.

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