code: function defineFixture(url, fixture) {
    if (fixture.response) {
      fixture.response = JSON.parse(JSON.stringify(fixture.response));
    }
    __fixtures__[url] = fixture;
  }
docs: /*
  Defines a fixture that will be used instead of an actual ajax
  request to a given url. This is useful for testing, allowing you to
  stub out responses your application will send without requiring
  libraries like sinon or mockjax, etc.
  
  For example:
  
  defineFixture('/self', {
  response: { firstName: 'Ryan', lastName: 'Florence' },
  textStatus: 'success'
  jqXHR: {}
  });
  
  @param {String} url
  @param {Object} fixture