KIAWAH ISLAND, South Carolina (Reuters) - Former U.S. Open winner Rory McIlroy spearheaded a glut of low scoring in ideal conditions to charge into a share of the early lead in Thursday's opening round of the PGA Championship. In dazzling sunshine with light breezes coming in off the ocean at Kiawah Island Golf Resort, the Northern Irishman fired a five-under-par 67 to hold the clubhouse lead ...