Dwight Howard has been on a tear this season, playing “at an MVP-type of level,” according to Mavericks coach Avery Johnson. Yet, Dirk Nowitzki is still the reigning MVP, and he reminded Howard and Johnson of it Monday night. Nowitzki scored 11 of his 31 points in the fourth quarter, including a surprisingly rare 3-pointer and a pair of free throws in the closing seconds to help send Dallas past…