PORTLAND, Maine — Motorists driving stretches of the Maine Turnpike will be allowed to go 5 miles per hour faster starting Monday, the Maine Turnpike Authority has announced.The speed limit will increase on the turnpike from 65 mph to 70 mph with the exception of three areas, Executive Director Peter Mills said.They are: south of mile marker 2.1 on I-95 in Kittery, where the maximum speed will remain 65 mph; through Greater Portland from mile marker 41 in Scarborough to mile marker 53 in Falmouth, where the speed limit will increase from 55 mph to 60 mph; and on the...