Two much-touted portions of the bill concerning health care start on Jan. 1. The soon-to-be implemented changes include a new inflation cap that limits how much drug manufacturers can change the price of prescription drugs and new rules that insure that people enrolled in a Medicare prescription drug plan don’t pay more than $35 for a month’s supply of insulin. The law also will allow many Medicare Part D beneficiaries to receive vaccines for $0 in the new year.   Another key