NIGERIA's President Muhammadu Buhari said he felt "overwhelming joy" over the news that kidnappers had released hundreds of schoolgirls in northwest Zamfara state unharmed. Earlier on today, state officials said gunmen had freed all 279 girls kidnapped from the Government Girls Science Secondary (GGSS) School in the town of Jangebe. In a Tweet, Buhari said he was "pleased that their ordeal has come to a happy end without any incident".  According to earlier reports, 317 girls from the Government Girls Science Secondary (GGSS) School in the town of Jangebe were abducted by an armed gang at around 1 a.m. on…