Persistence

Notifications are still on the old persistence system: This isn't actually breaking anything, but it's a very bad smell. And now that I'm adding userland ability to send notifications, it's going to become more problematic.

Rating Summaries not updating post-conversion?: In my dev "Simple Space to Convert", looking at "I'm an Instance!", the pre-conversion ratings were 4 and 2, and the _average was correctly set to 3.00. Post-conversion, I change the ratings to 4 and 5, but the _average is still 3.00. So something's getting lost.