anchor.diff:      test('first card is always legal move', () {
         Board board = new Board();
         for(CardDirection dir in CardUtil.allDirections){
  -        expect(CardUtil.allCards.every((card) => board.isLegalMove(BoardLoc.origin, card, dir)), isTrue);
  +        expect(Card.values.every((card) => board.isLegalMove(BoardLoc.origin, card, dir)), isTrue);
         }
       });
       test('legal cap card placement next to power station', () {
  
positive.code: 
    group('board isClosed tests', () {
      test('board with any one card is open', () {
        CardUtil.allCards.forEach((card) {
          Board board = new Board();
          board.playCardToStation(BoardLoc.origin, card, CardDirection.up, 1);
          expect(board.isClosed, isFalse);
  
negative.code:   group('card isPlayable tests', () {
      test('all cards are playable on an empty board', () {
        Board board = new Board();
        expect(Card.values.every((card) => board.isPlayable(card)), isTrue);
      });
      test('all cards are playable on a board with any one card played', () {
        Card.values.forEach((card) {
          Board board = new Board();
          //play a card to the station
          board.playCardToStation(BoardLoc.origin, card, CardDirection.up, 1);
          Card.values.forEach((card) {
            //any card is still playable
            expect(board.isPlayable(card), isTrue);
          });
  