External Controls for Dealing with Conflicting Updaters

[WilliamIX]

Consider the case when there are two processes A and B which by default each update a store X by setting.

Currently, the order A and B are added to the Bigraph determines which setter takes precedent. It would be very helpful to have a flag in the schema {path: {X : _update : False} which can be used to override the default schema to turn off updating from one of the processes or the other to remove this order dependence.