THIAM NDIAGA A national conference in Burkina Faso has authorised the ruling junta to hold power for three years, potentially setting the West African country on a collision course with international partners who have urged a speedy return to constitutional order. The junta seized power in a January coup against President Roch Kabore, blaming him for failing to contain surging violence by Islamist militants. The putsch was led by Lieutenant-Colonel Paul-Henri Damiba, who is now interim president. The charter was approved by the conference and signed by Damiba in the early hours of Tuesday after a day-long debate in the…