It wasn't quite "Mutiny on the Bounty," but it was as close as we get these days. Last week Gary Feener, captain of the 73-foot scallop boat Barnacle Bill, radioed for help claiming his crew attacked him about 100 miles off Nantucket The sailors complained of bad food, bad pay, bad treatment; the captain claims he was threatened with a scallop knife. He and two loyalists managed to lock themselves in the pilot house while the swashhuckling scallopers cut the navigational and electrical wires and trashed the deck. But this highseas adventure didn't end with a keelhauling. Captain Feener was rescued by the Coast Guard and the crew was ferried to nearby Hyannis.