ABRAHAM ACHIRGA AT a market in Nigeria's northern Kano state customers stocked up on food and essentials, uncertain of the outcome of Saturday's election to choose a new president and lawmakers, in a country where voting has sometimes been followed by violence. Shortages of cash and fuel and the highest inflation rate in nearly two decades have left Nigerians frustrated about the government of President Muhammadu Buhari, who is not on the ballot after serving the maximum two presidential terms. "We don't know what is going to be the outcome of the election so that is why you see everyone trying to come and…