old_contents: Kpcc.Article = DS.Model.extend({
      title           : DS.attr(),
      short_title     : DS.attr(),
      published_at    : DS.attr(),
      byline          : DS.attr(),
      teaser          : DS.attr(),
      body            : DS.attr(),
      public_url      : DS.attr(),
      assets          : DS.hasMany('asset'),
      audio           : DS.hasMany("audio"),
      category        : DS.belongsTo('category'),
  });
  
  Kpcc.ArticleSerializer = Kpcc.ApplicationSerializer.extend(
      DS.EmbeddedRecordsMixin, {
          attrs: {
              assets      : { embedded: 'always' },
              category    : { embedded: 'always' },
              audio       : { embedded: 'always' }
          }
      }
  )
  
new_contents: Kpcc.Article = DS.Model.extend({
      title           : DS.attr(),
      short_title     : DS.attr(),
      published_at    : DS.attr(),
      byline          : DS.attr(),
      teaser          : DS.attr(),
      body            : DS.attr(),
      public_url      : DS.attr(),
      assets          : DS.hasMany('asset'),
      audio           : DS.attr(),
      category        : DS.belongsTo('category'),
  });
  
  Kpcc.ArticleSerializer = Kpcc.ApplicationSerializer.extend(
      DS.EmbeddedRecordsMixin, {
          attrs: {
              assets      : { embedded: 'always' },
              category    : { embedded: 'always' }
          }
      }
  )
  
subject: Fix Reader to support non-model audio (no ID)