Reno's downtown Riverwalk District kicks off its first Art Walk from 4 to 9 p.m. on Thursday with live entertainment, art openings, fashion and jewelry and other special events.Planners say the Art Walk will happen on the last Thursday of the month from April through October.We have more than 40 merchants from which to choose, said Valerie Neish, president of the Riverwalk Merchants Association,