If I remove `done()` from the second unit test (The synchronous test) it times out after 2000ms.

```
    it('should ensure host header use matches that passed to proxy-out on require', function(done) {
      expect(headers).to.exist;
      expect(headers.host).to.equal(proxyParts.hostname);
      // done();
    });
```

```
  proxy-out
    http.get
      ✓ should be able to connect to google via the supplied proxy
      1) should ensure host header use matches that passed to proxy-out on require


  1 passing (2s)
  1 failing

  1) proxy-out http.get should ensure host header use matches that passed to proxy-out on require:
     Error: timeout of 2000ms exceeded
      at null.<anonymous> (/Users/rrowland/git/proxy-out/node_modules/mocha/lib/runnable.js:175:14)
      at Timer.listOnTimeout [as ontimeout] (timers.js:110:15)
```