serializer.js

App.ApplicationAdapter = DS.RESTAdapter.extend({
  host: 'https://api.github.com',
  headers: {
    authorization: 'basic ' + btoa(username + ':' + password)
  },
  serializer: DS.RESTSerializer.extend({
    extractArray: function (store, primaryType, payload) {
      var o = {};
      o[this.pluralize(primaryType.typeKey)] = payload;
      return this._super(store, primaryType, o);
    }
  }).create()
});