By Ira Teinowitz LOS ANGELES (TheWrap.com) – The "Homeland" cast and crew got a lesson in Top Secrecy from the CIA on Monday. The Showtime spies met the real spies in a three-hour afternoon visit to the Central Intelligence Agency on its Langley, Virg., campus. What did they discuss? Well, they'd tell us … but then they'd have to kill us. "I'm not allowed to talk about what we talked about — and I'm not kidding," showrunner and executive producer Alex Gansa told TheWrap. But he would admit that the agents had a few technical issues with the show. …