launchpad proxy support

[Gordon Tyler]

Vincent Ladeuil wrote:
> Hmm, I was wrong, now that I've looked at the code
> _urllib2_wrappers can even take care of that...
> 
>     >> You want to look at test_http among others, but be aware that we
>     >> *don't* have a proxy test server, we fake one for test purposes
>     >> but I don't think you can reuse it.
> 
>     Gordon> Hmm... Why do I think the tests are going to be the hardest part
>     Gordon> of all this? ;)
> 
> Yeah, that's why I delayed fixing that bug so long :-/
> 
> I'll have a simple fix with tests shortly, 

I've got some refactored code which puts the transport classes in 
lp_registration.py, with a little abstraction to separate HTTP from 
HTTPS, which I can push up to lp later this evening if you want. I was 
trying to separate the code paths but I hit the snag in the urllib2 
wrappers that you probably found.

Ciao,
Gordon