By Mukala Kabongo NEFJ Staff NORTH ANDOVER — Sacred Heart used a strong second half to outlast Merrimack, 31-20 in the inaugural Yankee Conference Championship on Saturday. It was senior day at Duane Stadium for the host Warriors (4-6) and a day where Merrimack had the opportunity to close out its home schedule with a win and a 'conference' crown paying homage to the old days. However, Sacred Heart (5-6)...