Fix for name or service unknown

A connection format must be specified. Otherwise, I have been receiving a name or service unknown error.

```
Traceback (most recent call last):
File "./my-python-script.py", line 111, in <module>
bucket = conn.create_bucket(bucket_name)
File "/usr/lib/python2.6/site-packages/boto/s3/connection.py", line 434, in create_bucket
data=data)
File "/usr/lib/python2.6/site-packages/boto/s3/connection.py", line 470, in make_request
override_num_retries=override_num_retries)
File "/usr/lib/python2.6/site-packages/boto/connection.py", line 913, in make_request
return self._mexe(http_request, sender, override_num_retries)
File "/usr/lib/python2.6/site-packages/boto/connection.py", line 859, in _mexe
raise e
socket.gaierror: [Errno -2] Name or service not known
```