Whole Foods Market, which has been changing the supermarket landscape in North Jersey in the 15 years since it opened its first store in Bergen County, is preparing to roll out a new concept for price-conscious consumers that could present a fresh challenge to traditional grocery chains. Austin, Texas-based Whole Foods Market Inc. is rolling out the first new-concept stores, called 365 by Whole Foods Market, close to its home base in Texas and one on the West Coast.