title: Issue with getting Nock response into call function
body: <p>I just started using nock to intercept http calls. Below is the code I am using in a unit test case after importing the required modules.</p>
  
  <pre><code>it('testing superagent using nock..', function () {
  
      let mockData = {
          scope: this,
          data: {"title":"test"},
          callback: function (data){
              //expecting {id:10} here.but nothing is coming
              console.log(data)
          },
          errback: function(err) {console.log(err)}
      };
  
      nock('http://localhost').post('/api/1234').reply(200, {id: 10});
  
      callFunction(actionFunction, mockData, this);
  }
  </code></pre>
  
  <p>callFunction sends the parameters 'actionFunction', 'mockData' to another class where actionFucntion takes mockData and makes ajax request using superagent module.</p>
  
  <pre><code>import xhr from './xhr';
  static  actionFunction(mockData){
  let xhr = mockData.xhr || xhr;
  xhr.reqXhr({
  method: :"POST",
  url: mockData.url,
  data: mockData.data,
  callback: function(data) {mockData.callback.call(mockData.scope, data);},
  errback: function(response) {mockData.errback.call(mockData.scope, response);}
  })
  }
  
  //in xhr class I am triggering the actual ajax call using super agent
  
  super-agent(method, url).send(reqdata).end((errror, response) =&gt; {
      //sending response.body to call backs similar to below
      request.callback.call(this, response.body);
      }
  </code></pre>
  
  <p>Now the issue is though nock was able to intercept the http call, nock mock response ({id:10}) is not reaching callback function. I would like to display this response in call back function</p>
  
  <p>any possible way to do this?</p>