Oh, no big deal, it’s just a marijuana get-together. A bunch of guys are chatting, about weed, yes. But the talk is also about revenue, and futures, and even the NASDAQ. Turns out, we’re at a convention center for a business expo on cannabis. And it’s crawling with straight-laced financiers and ex-Wall Streeters. The host, Scott Greiper — a former analyst and New York banker who’s president of Viridian Capital Advisors, the country’s first advisory firm and investment bank t