NASCAR is expanding its Chase format to include its feeder series.    NASCAR Chairman and CEO Brian France announced Tuesday that the Xfinity Series and the Camping World Truck Series will begin using a Chase format in 2016, mostly mirroring the playoff-style setup used to determine the Sprint Cup champion the last two years.    The lower-tier series will feature a seven-race Chase to decide its champion. The Cup series uses a 10-race format.    All three series will crown a champ at Homestead-Miami Speedway. However, all three will begin at different tracks: Chicago (Sprint Cup), Kentucky (Xfinity) and New Hampshire (Trucks).