Provide services to abstract store from business logic

controller/api/initialise_test.go

controller/interfaces/device/device.go

controller/interfaces/device/deviceService.go

controller/interfaces/device/deviceStore.go

controller/interfaces/southbound/Service.go

controller/interfaces/southbound/sbi.go

controller/interfaces/southbound/sbiStore.go

controller/northbound/server/pnd_test.go

controller/nucleus/databaseDeviceStore.go

controller/nucleus/databaseSbiStore.go

controller/nucleus/deviceService.go

controller/nucleus/deviceService_test.go

controller/nucleus/deviceStore.go

controller/nucleus/errors/errors.go

controller/nucleus/genericService.go

controller/nucleus/initialise_test.go

controller/nucleus/memoryDeviceStore.go

controller/nucleus/memorySbiStore.go

controller/nucleus/principalNetworkDomain.go

controller/nucleus/principalNetworkDomain_test.go