CAIRO (AP) — Famine . Massacres . And now badly needed food and other supplies are under strain. Sudan on Wednesday enters a fourth year of war that’s being called an “abandoned crisis,” as a new conflict in the Middle East throws into shadow the fighting that has forced 13 million people to flee their homes. Sudan has been described as the world’s largest humanitarian challenge, notably in terms of displacement and hunger. There is no end in sight to the fighting between the military and the