Initially underrated, Forte quickly became invaluable at every level By LENNY VANGILDER, Written for the LSWA Recruiting services listed Matt Forte as a fullback coming out of Slidell High School. He would make his mark over four years at Tulane and 10 more in the NFL as a lead back. To his former high school coach, Wayne Grubb, the letters next to his name didn’t matter. “I always referred to…