By Ece Toksabay SILIVRI, Turkey (Reuters) - Turkish prosecutors summed up their case on Monday against those accused of plotting to overthrow Prime Minister Tayyip Erdogan's government, seeking life terms for an ex-military chief and other retired generals. Retired armed forces commander Ilker Basbug was among 275 defendants whom prosecutors accused of attempting to stage a coup as part of the "Ergenekon terrorist group", an alleged underground network of secular arch-nationalists. Erdogan's ruling AKP party has Islamist roots. ...