Getty Images Aliko Dangote made his money through sugar and cement Petrol production at Nigerian business tycoon Aliko Dangote’s $20bn (£15.5bn) state-of-the-art oil refinery ought to be some of the best business news Nigeria has had in years. But many Nigerians will judge its success on two key questions – firstly: “Will I get cheaper petrol?” Sorry, but probably no – unless the international price of crude drops. And secondly: