By Andrew Osborn (Reuters) -A Russian state prosecutor asked a Moscow court on Thursday to jail prominent nationalist Igor Girkin, who accuses President Vladimir Putin and the army top brass of not pursuing the Ukraine war effectively enough, for nearly five years. State prosecutors accuse Girkin, who is regarded in the West as a war criminal over the 2014 shooting down of a passenger plane over eastern Ukraine, of inciting extremism, something he denies. His case is being closely watched as an indication of how far the Kremlin will tolerate aggressive criticism of its war effort in Ukraine, s…