var defaults = [
  {
    title: 'iPad 2',
    ch: {
      dpr: '1.0'
    }
  },
  {
    title: 'Nexus S',
    ch: {
      dpr: '1.5'
    }
  },
  {
    title: 'Nexus 4',
    ch: {
      dpr: '2.0'
    }
  },
  {
    title: 'Nexus 4 (160px image width)',
    ch: {
      dpr: '2.0',
      dw: '160'
    }
  }
];

var defaults = [
  {
    title: 'iPad 2',
    ch: {
      dpr: '1.0'
    }
  },
  {
    title: 'Nexus S',
    ch: {
      dpr: '1.5'
    }
  },
  {
    title: 'Nexus 4',
    ch: {
      dpr: '2.0'
    }
  },
  {
    title: 'Nexus 4 (160px image width)',
    ch: {
      dpr: '2.0',
      rw: '160'
    }
  }
];

Update CH-DW -> CH-RW to match latest spec
Update CH-DW -> CH-RW to match latest spec
