HARARE (Reuters) - Two armoured personnel carriers were positioned on the outskirts of Zimbabwe s capital late on Tuesday and soldiers were directing traffic, a Reuters witness said, a day after the head of the army threatened to intervene in politics. The soldiers deployed on Harare Drive, a major thoroughfare, ordered passing cars to keep their windows up and not ask questions.  Don t try anything funny, just go,  one soldier said to a Reuters reporter. 