preliminary py3k compat; nicer response parsing; moved instance attrs to...

Hi.

Thanks for working on the package.

I made some quite aggressive changes and on the way added (hopefully working) py3k compat. I hope I haven't introduced any obvious bugs around encoding/decoding with py3k style bytes vs unicode strings.

On the subject of py3k, I haven't been able to test with versions pre-3.2.

Feel free to reject this commit out of hand; especially because it's just one giant change-set. This pull request is really just a big thank you for your work on the module.

Best xxx