code: function getPositionWhereCanIGoFromArray(isBlack, positions) {
      const { x, y } = getPositionFromArray(R.head(positions));
      return {
          x, y, isBlack,
          whereCanIGo: R.tail(positions).map(getPositionFromArray)
      };
  }
docs: Gets an array like [[0, 7], [0, 6], [1, 6]],
  where [[positionX, positionY], ...[[whereCanIGoX, whereCanIGoY]]]
  then returns IPiece.
  
  Used to create clean test data.