Access Control/Authorized User support

I'm not sure if this is an improvement, bug, or what...

It seems that when you create a calendar, you're the only person that can edit it. In the short term this is problematic for me; in TEAMCAL-119 I asked how to reassign calendars to other owners (officially or unofficially) so that at least I can have the right people responsible for the manually-imported-from-the-old-calendar-plugin calendars able to edit them.

However, there are two very distinct differences from the old system that are really going to be problematic:

1) Having multiple users able to edit a calendar. Previously if you could edit a page, you could edit the calendar. We really need to be able to emulate this behavior.
2) Having the ability to restrict calendar viewing/editing to a subset of people. Previously if you couldn't get access to a page, you couldn't see the calendar. We also really need to be able to emulate this behavior.

To me these are very critical security issues, because the upgrade path (3.5 doesn't support the old plugin, migrate to this one) doesn't mention that these controls are now lacking, and as a result we now have to either have some of our calendars be unusable until such a time as these controls are back or we have to make public some calendars that we don't really want public.