Decide on event-classes ("members-only" / "invite-only" / "inner-circle-only" / "open") and how to label / show them.

[reinhrst]

We need to make a list of which labels we want, and what rules we want to apply to each label (and maybe what default to events that don't have a label).

e.g. inner-cicrle-only events are not shown on /events page; default events calendar contains only "open" events, etc.