Use proper API in http_to_file

[dgilman]

http_to_file() in twitter_utils.py gets data out of the Response object as Response.raw.data which is a property from the underlying urllib3 library that doesn't do the proper decoding. If the server sent gzipped data it won't be decompressed. Response.content should be used instead as it handles the decoding for you (see https://github.com/requests/requests/blob/master/requests/models.py#L724 , decode_content=True)

[jeremylow]

Fixed in 2bf461f

Thanks!