Tonight @ U.S. Cellular Connection Stage, Summerfest, 10 p.m. The most divisive musical phenomenon of 2009, Asher Roth emerged from practically out of nowhere with his debut single “I Love College,” an unforgettable introduction that laid out Roth’s M.O.: He loves college, he loves drinking, he loves smoking, he loves women. He’s that college guy. That track put Roth’s name out…