Response inherits from Stream instead of Stream.Readable (requiring request module browserify workaround)

On node.js, the HTTP response object (which is named IncomingMessage in node.js) [inherits from Stream.Readable](https://github.com/request/request/commit/6ebd748a02a49976d41ebbc4f8396acf8fda1c14):

``` javascript
util.inherits(IncomingMessage, Stream.Readable);
```

but in http-browserify, it [only inherits from Stream](https://github.com/joyent/node/blob/1781c8b85bbabc4c5c1e054bd5c50903cc0eb47b/lib/_http_incoming.js#L80):

``` javascript
util.inherits(Response, Stream);
```

This means the full stream API is not available as it is in Node, including the [.resume](http://nodejs.org/api/stream.html#stream_readable_resume)() method. I believe this is the reason for [this ](https://github.com/request/request/commit/6ebd748a02a49976d41ebbc4f8396acf8fda1c14) [hack](https://github.com/request/request/blob/a60482bf06b7e16d3cdbabcdee7f0b62d93117c2/request.js#L973-975) in the [request](http://github.com/request/request) module:

``` javascript
} else if (response.resume) {
// response.resume should be defined, but check anyway before calling.
// Workaround for browserify.
response.resume()
}
```

to improve compatibility would it be possible for http-browserify Response to inherit from Stream.Readable? (are there any other changes needed than changing the utils.inherits call?)

edit: Stream is old-style (pre-0.10); this amounts to converting http-browserify to [Streams2](https://rawgit.com/rvagg/rvagg.github.com/master/2014/06/why-i-dont-use-nodes-core-stream-module.html)

Beginne bei der Definition von Response in http-browserify und ihrem Aufruf von util.inherits und vergleiche sie dann mit der in der Issue gezeigten Vererbung von Nodes IncomingMessage. Prüfe den Workaround in request.js und ermittle, ob die Umwandlung von Response in Streams2 Änderungen über die Vererbung hinaus erfordert. Fertig ist die Aufgabe, wenn die Browser-Response die erwartete Readable API einschließlich resume() bereitstellt, ohne diesen Kompatibilitäts-Workaround.

Vom Indexierungsmodell aus dem Issue-Text verfasst.