MEXICO CITY (Reuters) - Mexico's top court freed a Frenchwoman convicted of kidnapping on Wednesday, ruling that her trial was tainted and ending a seven-year prison ordeal that strained diplomatic ties. Florence Cassez, 38, was serving a 60-year sentence that opened up a rift between France and Mexico after she was arrested in 2005 at a ranch near Mexico City with her former boyfriend, who led a kidnapping gang called the Zodiacs. Supreme Court Judge Jorge Pardo ordered her immediate release during a televised court session, which at one point looked to be going against her. ...