by Quendrith Johnson   When Ellen Page tells you she "was playing it cool on the inside" meeting with Brit Marling ("Arbitrage") and Sundance darling director Zal Batmanglij, you have to wonder what all the fuss is about.  To hear Zal tell it, "when I heard Ellen Page wanted to meet with us..." The movie in question, "The East," premiered last night in Hollywood at the ArcLight to an adoring hometown crowd, uh, hometown of Hollywood,...