look at returning responses

[GoogleCodeExporter]

It's kind of weird that there are currently three potential ways of
returning a response: 
1) return it from #responseForContext:/#handleRequest:
2) signal a WAResponseNotification
3) store it in WARequestContext's response instvar (this instvar is not
current accessed anywhere but the response is stored there)

We should ideally only be using one? Can we remove the instvar?

The response *stream* needs to be passed in the request context when using
a streaming server but this could be a separate subclass of
WARequestContext for streaming servers. This would actually be cleaner
because the request contexts could implement #newResponse or something so
that you would get a StreamingResponse instead of a Response for a
streaming server. Currently, WASessionContinuation>>newResponse has to
check whether #responseStream is nil.

Original issue reported on code.google.com by jfitz...@gmail.com on 9 Nov 2008 at 8:10