Comedian and “Daily Show” host Jon Stewart tore into former President Donald Trump on Monday evening, following the first day of his historic criminal trial in Manhattan. In particular, Stewart lambasted Trump for his campaign-rally tribute in Pennsylvania to the Battle of Gettysburg, one of the most famous campaigns of the Civil War — which he apparently didn’t know the first thing about. “If you thought Lincoln consecrated Gettysburg with his soaring rhetoric, well, buckle up,” he said before playing the clip. “Gettysburg, what an unbelievable battle that was,” said Trump on Saturday. “The B…