Chris Cornell @ The House of Blues, Saturday, Mar. 28Dude has been making music for 25 years! A pioneer of grunge, Cornell was the vocalist (and drummer up until 1986) for Seattle-based band Soundgarden. After the group disbanded in 1997, Cornell went on to work with former Rage Against the Machine members (sans vocalist Zack de la Rocha) in Audioslave. Today, he's doing his own thang. Meanwhile, did you know that Soundgarden was named after a public work of art in Seattle made of pi