HOLLISTON - If you're young and ride a bicycle through town without a helmet, you may end up walking back home. Police here are looking for scofflaws and will snatch the pedals from your feet if you've been warned numerous times but still forgo headgear.Holliston police, frustrated in trying to drive home the point that riding without a helmet is dangerous and illegal, are hoping the tactic will finally get the attention of young riders."We're not looking to take bikes away from the kids who forget their helmets," School Resource Officer David Gatchell said yesterday. "This isn't something where we're...