Louis Gerstner in 1996.Photographer: Suzanne Opton/The Chronicle Collection/Getty ImagesLouis Gerstner, who took over International Business Machines Corp. when it was on its deathbed and resuscitated it as a technology industry leader, died Saturday. He was 83.IBM chairman and CEO Arvind Krishna announced Gerstner’s death in an email sent Sunday to its employees, but didn’t provide a cause of death....