Choosing whether or not to receive Comment Notifications should work immediately

(Bug, To be Fixed , Priority: High, Test Status: No automated tests yet , Reported By Justin du Coeur, )
Notifications
Summary: Currently, if you go to Actions -> Advanced... and choose to receive Comment Notifications, it doesn't take effect until the Space next reloads. That's annoying.
The reason for this bug is that the Actor that tracks who gets them doesn't have a way to listen to changes in this property. Fixing it probably requires introducing some sort of "property listener" mechanism.