Cleaned up requestResponse spec

We could improve this test by seeing if it calls `reqres.request` with the right context.

```js
beforeEach(function() {
  this.requestName = 'foo';
  this.argOne = false;
  this.argTwo = 'bar';
  this.requestSpy = this.sinon.spy(app.reqres, 'request');
  app.reqres.request(this.requestName, this.argOne, this.argTwo);
});

it('should call reqres.request with the same arguments and correct context', function() {
  expect(this.reqresSpy)
    .to.have.been.calledOn(app.reqres)
    .and.calledWithExactly(this.requestName, this.argOne, this.argTwo);
});
```