Increasing the maximum term of imprisonment for the offense of manslaughter by vehicle or vessel from 10 to 20 years, and from 15 to 30 years for an individual who has previously been convicted of certain other driving-related offenses, and the maximum term of imprisonment for the offense of homicide by motor vehicle while under the influence of alcohol or alcohol per se from 5 to 10 years, and from 10 to 15 years for an individual previously convicted of certain other driving-related offenses.