CSS Fonts Module Level 4: Support font-weight ranges in @font-face declarations

[papandreou]

#5 caught this case:

it('should support a font-weight range', function() {
  const snapped = snap(
    [
      {
        'font-family': 'foo',
        'font-weight': 'bold 734'
      },
      {
        'font-family': 'foo'
      }
    ],
    {
      'font-family': 'foo',
      'font-weight': 'bold'
    }
  );

  expect(snapped, 'to satisfy', {
    'font-weight': 'bold 734'
  });
});