Kids playing at a school playground discovered 15 nails at the bottom of a slide Wednesday morning, apparently placed there with the express intent to hurt someone, authorities said. The 1-inch nails were found in a playground on the grounds of Glen Yermo Elementary, a school located at 26400 Trabuco Road, said Jim Amormino, spokesman for the Orange County Sheriff's Department. Jim Amormino, of the Orange County Sheriff's Department, holds the roofing nails that were found on the playground at Glen Yermo Elementary School on Trabuco Road in Mission Viejo, Wednesday morning. "This is a serious crime…