By Tom Hals (Reuters) – A lawsuit filed last week accusing the National Football League of racist hiring practices brought to light allegations that owners secretly offered incentives to coaches to lose, which could lead to class action lawsuits for hundreds of millions of dollars and even criminal liability, experts said. The accusation comes at a time of explosive growth in legal sports gambling and just over a week before the league’s Super Bowl extravaganza. The two teams at the center of the claims – the Miami Dolphins and Cleveland Browns – have denied the allegations that they wanted th…