By Thiam Ndiaga and Anne Mimault OUAGADOUGOU (Reuters) -Gunfire rang out across Burkina Faso’s capital on Saturday and fire broke out at the French embassy after self-declared leader Ibrahim Traore accused President Paul-Henri Damiba of staging a counter-offensive after his apparent ouster a day earlier. The standoff signals deep division within the army and a worrying new chapter for Burkina Faso, where a rampant Islamist insurgency has undermined faith in the authorities and displaced almost 2 million people, according to aid groups. The West African country and former French protectorate ha…