Sandbox.Event

A Type with events on it

A method on a type

Run this event action, aggregating any exceptions.

A list of events, usually indexed by the event name

Run this event list, aggregating any exceptions.

Instances that have had their assembly removed. We keep them around becuase the assembly might be re-registered.

Register an assembly. If old assembly is valid, we try to remove all of the old event hooks from this assembly, while retaining a list of objects.