Nuggets G Smith says jail changed him (AP)

J.R. Smith is pledging more maturity this season, a promise he's made in the past. The sharp-shooting Denver Nuggets guard realizes that some will believe it, while some will remain skeptical. That's fine with him. He knows he's changed. It's been a sobering offseason for the 24-year-old Smith, who spent 24 days in a New Jersey correctional facility after pleading guilty to reckless…