ÉVIAN-LES-BAINS, France — After several years of lurking in the shadows, the specter of doping once again looms over the Tour de France. Though nobody has tested positive—or no positive test results have been made public—the biggest story at this year's Tour is a renewed aggression from testing authorities and a resultant increasing hostility from the riders. The tactics executed by anti-doping officials and the legal justifications marshaled to…