CHICAGO >> Scott Frost talks to Tom Osborne almost every week. He welcomes his college coach into his office at Nebraska, or they go turkey hunting or fishing.Hard at work at rebuilding his storied alma mater, Frost is keeping his friends as close as possible.The 43-year-old Frost is home again after a successful run with Central Florida, returning to Lincoln in December after coaching the Knights to a 13-0 record last season.