Central Michigan's David Bolyard has been named the Mid-American Conference Wrestler of the Week.    Bolyard won the Midlands Championships at 165 lbs. by defeating 10th-ranked Ralph Everett of Hofstra in the finals, 2-1 in double overtime.    To reach the finals, Bolyard defeated fourth-ranked Nick Passalano of Iowa State in the semifinals, 5-3.    Bolyard is now 16-3 this season and ranked fifth in the nation.