A genial comedian who skewered the foibles and contradictions of everyday life in his act, Jay Leno’s everyman persona and tireless work ethic – he played up to 300 shows a year – helped to earn him one of the most sacred spots in television: the replacement for Johnny Carson as host of “The Tonight Show” (NBC, 1954- ). The ascension was not without its rough patches – he found himself in the middle of a behind-the-scenes firestorm when both he and David Letterman vied for Carson’s seat, and after taking over the show, he was frequently criticized by pundits and fellow comics alike for dulling