This can't be done in Django 1.7. `INSTALLED_APPS` can be an appconfig.

A way to do that would be to ask mezzanine users to create [their own `AppConfig` and override `ready()` and put their defaults here](https://docs.djangoproject.com/en/dev/ref/applications/#django.apps.AppConfig.ready). And only run this code for Django < 1.6.

Another way, (I'm not a big fan of this one) would be to create an `AppConfig` for `mezzanine.conf` and iterate over `django.apps.app` in `mezzanine.conf.Appconfig.ready()`.

What do you think @stephenmcd?