Fixed minor error with defendersList on reboot.

Fixes:

java.lang.NullPointerException
at resources.objects.tangible.TangibleObject.getDefendersList(TangibleObject.java:328)
at services.gcw.FactionService.calculatePvpStatus(FactionService.java:318)
at resources.objects.creature.CreatureObject.sendBaselines(CreatureObject.java:1475)
at engine.resources.objects.SWGObject.makeAware(SWGObject.java:532)
at services.SimulationService.add(SimulationService.java:251)
at services.SimulationService.handleZoneIn(SimulationService.java:1187)
at services.object.ObjectService$7.handlePacket(ObjectService.java:1169)
at engine.resources.service.NetworkDispatch$1.run(NetworkDispatch.java:216)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)