Prosecutors were presenting their bribery case against New Jersey Sen. Bob Menendez drip-by-drip on Tuesday, showing jurors a steady stream of documents, emails and phone records that they’ll explain more thoroughly later in the trial. The evidence was being shown to Manhattan federal court jurors through the testimony of an FBI agent as the government slowly presents its case against the Democratic lawmaker. Menendez, 70, is on trial with two New Jersey businessmen who prosecutors say paid him bribes, including gold bars and cash, over the last seven years so that he’d use his power as a sena…