After a syncdb or migrate, django_evolution.management attempts to

record new state in the database, but it only does so once the

django_evolution app and its tables have been made available in the

database. For this, it needs a reference to the app, which was being

done at module initialization.
It's possible for this code to run too early, before other apps are

properly set up, which could cause failures either fetching the app or

from some logic within the app.
To avoid this, we now lazily fetch the app the first time we need it,

caching it for future reference.

Unit tests pass.
Successfully created new databases and upgraded existing ones.