A survey commissioned by Twin River Management Group says 60-percent of Tiverton residents support plans for a casino there.  Earlier this year Twin River announced it wants to build a casino in Tiverton.  It plans to buy and close the Newport Grand Slots Parlor, and transfer the existing license to the new casino.  "The Providence Journal" also reports the chairman of Twin River Management says he's committed to developing the proposal with advice and guidance from the community.