We heard it through the grapevine - Queens has a purple pigeon. The royal-hued bird wasn't born that way, though. Someone with a sick sense of humor - or a problem with pigeons - painted him purple. "Itwas terrible," said Joe Mora, an animal lover who rescued the birdThursday from a Long Island City playground, where onlookers were gawking at the oddly-colored columbine. "It looks like this was done intentionally...it could have been blinded," Mora said. He tried coaxing the lethargic bird to eat while asking anyone and everyone for advice on how to clean paint from its feathers and...