By Erik Kirschbaum LEIPZIG, Germany (Reuters) - Bruce Springsteen jumped off the stage and into a frenzied German crowd of 45,000 fans on Sunday in Leipzig to pluck a sign with a hand-written request scrawled on it - as he has been doing all summer on his popular tour across Europe. But when Springsteen whirled around and held up the name of the song for his band to see, jaws dropped and a frightened look crossed their faces. The sign read "You never can tell" by Chuck Berry, a 1964 tune made popular in the 1994 film "Pulp Fiction. ...