By Daniel Kline Sin City has become Sports City and the owner of an iconic casino might make a surprise deal to bring another major pro franchise to the Las Vegas Strip. For decades every professional sports league treated gambling, and by extension Las Vegas, as some sort of demon that might bring their sport down. Broadcasters never talked about things like point spreads or favorites ignoring what was a multi-billion dollar industry that just happened to be mostly illegal. Now, since the Supreme Court pushed the question of legalizing sports betting to the states, every major sports league i…