DATABASE_ROUTERS is not defined normally in default.py. As such when you disable an app with DISABLED_APPS ian exception is raised in settings.py as it tries to access DATABASE_ROUTERS.
This fix just wraps that section in an:
if 'DATABASE_ROUTERS' in local()
Adding the templating caching template finder for non-local deployments
Adding a clause around the DATABASE_ROUTERS section of app disabling …
…as DATA_ROUTERS may not be defined.
I cherry-picked the DB commit onto master.