Jon Stewart’s return to “The Daily Show” has brought more than just laughs and biting political commentary.On the Feb. 26 episode of the Comedy Central late-night show, Stewart turned very serious when he announced the death of his dog, Dipper.Stewart, who is hosting Monday night episodes of the show, said the pit bull entered his family’s life when his kids wanted to raise money for a New York City animal shelter about 12 or 13 years ago and they set up a table outside the facility to sell cupcakes.“As a little extra incentive, they brought out this 1-ish-year-old brindle pit…