kennethreitz/requests — pull request #820 by dergraf (2012-08-29 19:29:28+00:00)
Title: Data encoding should take place after calling into auth provider

I discovered this bug when using the auth.OAuth1 auth provider. If I did a simple
```python
oauth = OAuth1(key,secret,signature_type=SIGNATURE_TYPE_BODY)
requests.post(url, data={'some':'param'}, auth=oauth)
```
only the data {'some':'param'} gets transmitted, all the OAuth specific parameters aren't packed into the body.

My patch moves the data encoding after the calling into the auth provider.