A Queens imam pleaded guilty Thursday to lying to feds who were investigating whether he tipped off wannabe terrorist Najibullah Zazi that he was being watched. Ahmad Afzali faces six months in prison and deportation 90 days later under the plea deal - which he said amounts to an execution. "I just signed my death sentence," the Afghan national said outside court, explaining that he has no idea where he would go after leaving the United States. "I'm between a rock and a wall." Afzali lost his composure several times during the proceeding before Brooklyn Federal Judge Frederic Block, wiping...