SAN FRANCISCO — Thousands of rainbows appeared under the blue sky yesterday as an estimated half-million people lined the streets to celebrate diversity and progress during the city's 32nd annual gay-pride parade. The people were just as colorful as the flags they waved — gay, straight, young and old. Some wore leather or feathers or held balloons, while others sported little more than a smile. The Dykes on Bikes, a rumbling motorcade of several hundred women on motorcycles, kicked off the event, followed by their quieter, male counterparts pedaling bicycles as part of the Mikes on Bikes. But mixed in...