Plugins let you register handlers that help initialize an actor upon start up. We are currently using this for the Stashing support.
Instead of providing AbstractUntypedStashedActor, AbstractTypedStashedActor, AbstractYaddaYaddaStashedActor etc. (F# versions etc) We can instead apply an interface to the actor type, and let the framework inject extra state holders and such. it's sort of a poor mans Mixins