* President has ordered a reshuffle of military command
* Islamists remain grave threat to Africa's top oil exporter
By Ibrahim Mshelizza
MAIDUGURI, Nigeria, Jan 20 (Reuters) - Islamist militants stormed a village in remote northeast Nigeria on Monday, torching houses and spraying them with bullets in an attack that killed 18 people, witnesses said.
The latest Boko Haram assault, on ...