Clint:A Retrospective by Richard Schickel, introduction by Clint Eastwood; Sterling, 288 pages plus 20-minute profile on DVD($35). The 80th birthday of Clint Eastwood came and went with surprisingly little fanfare a month ago. Oh sure, there was the requisite observance on Turner Classic Movies, but there was no significant pause in America's cultural machinery to ponder this significant fact:We have never before had an active, hit-making director/producer/superstar to hit 80.