Out of all of Hanna-Barbera's classic cartoon characters, none have the incredible staying power of Yogi Bear.Warner BrothersIntroduced in 1958 as a character on The Huckleberry Hound Show, Yogi's pic-a-nic basket-stealing antics have never gone out of style, and odds are his cartoons are still in syndication on one of your local channels. Which is why it can be so surprising to learn that a revamped '90s spin-off starring Yogi helped kill America's Saturday morning cartoon tradition.NBCYo Yogi! ran in NBC's Saturday morning lineup for just 19 episodes in 1991, but it had a huge impact on cartoon