Updated VIF creation in GUI, validation and check if completed is now run on temporary XDocument before writing to the actual file

Added Factory Method to SimulatorFactory class (this way the testcases where simulator factory was created without Ninject don't break), made simulatorFactory abstract and derived SimulatorFactoryEngineering and SimulatorFactoryDeclaration.

Added VehicleTypeApprovalNumber in XMLVehicleWriter, InterimStageBusVehicleViewModel and VehicleView_v2_8

Added VehicleTypeApprovalNumber to IVehicleDeclarationInputData and implemented Property in all derived Types (throw NotImplementedException)