[OPR-133]: Provides internal cancelled state
[OPR-133]: Provides internal cancelled state

This fixes a bug in NSOperation where cancelled operations would not correctly trigger their isFinished KVO notification.

danthorpe/Operations,blg-andreasbraun/ProcedureKit,blg-andreasbraun/Operations,danthorpe/Operations,cezarywojcik/Operations,blg-andreasbraun/ProcedureKit,ProcedureKit/ProcedureKit,cezarywojcik/Operations,blg-andreasbraun/ProcedureKit,cezarywojcik/Operations,danthorpe/Operations,blg-andreasbraun/Operations,blg-andreasbraun/Operations,ProcedureKit/ProcedureKit,ProcedureKit/ProcedureKit