By JONATHAN MATTISE and MARK HUMPHREY COLLIERVILLE, Tenn. (AP) — A gunman attacked a grocery store in an upscale Tennessee suburb on Thursday afternoon, killing one person and wounding 12 others before he was found dead of an apparent self-inflicted gunshot wound at the store, authorities said. Collierville Police Chief Dale Lane said the shooting broke out at a Kroger grocery in Collierville, a suburban