The Packers have added another undrafted free agent to the roster. And Dimitri Stanley has a rich Green Bay background. The Packers, who started rookie minicamp on Friday, added the former Iowa State receiver after a two-day tryout. The news was first reported by Tom Silverstein, who covers Green Bay for the Milwaukee Journal Sentinel. Stanley is the son of Walter Stanley, who was a receiver and ace returnman for Green Bay from 1985-88. Packers coach Matt LaFleur singled out Stanley after the first day of rookie camp. “We had one guy who had a one-handed grab out there that was pretty impressi…