Two years after the Philippine city of Marawi was overrun by jihadists it remains in ruins, with experts warning that stalled reconstruction efforts are bolstering the appeal of extremist groups in the volatile region.The 23 May, 2017 invasion by gunmen waving the black flag of the Islamic State (IS) group sparked a five-month battle that shattered swathes of the southern city.Demolition of blast-pocked buildings has finally begun, but after several false starts the government does not expect