Pennsylvania Governor Tom Corbett has signed a bill aimed at making driving safer for people with junior licenses. It increases the amount of supervised time teen drivers need behind the wheel before they can get a license, limits the number of underage passengers they can carry to one in the first six months after they get a license, and makes not wearing a seatbelt a primary offense for anyone under the age of 18.  At Tuesday’s bill-signing ceremony, he thanked Bucks County State Representative Kathy Watson and Montgomery County State Senator John Rafferty, who were the primary sponsors in their respective chambers of the legislature.