NELSON A. ROCKEFELLER, JR. PARK     North end of Battery Park City, west of River Terrace.   Rockefeller Park contains most of BPC Parks' wide lawns, as well as a large playground, plantings and gardens, several public art pieces, and a sheltered pavilion. Restrooms and public telephones are located at the Park House, off RiverTerrace between Murray Street and Park Place West, where BPC Parks staff are also available to provide assistance and information.