Papua New Guinea, an impoverished South Pacific nation that joined the ranks of the world’s significant energy exporters five years ago, installed a new prime minister who has called for greater local control of resources, in a move that may upset a gas deal with international energy giants. The new prime minister, James Marape, was elected by lawmakers on Thursday to succeed Peter O’Neill, who led the resource-rich nation for seven years and stepped down this week amid intensifying political unrest and government defections. …