CURL_INFO_HTTP_CODE should return an integer not a string

[adrfonseca]

Hi,

First of all, great lib that makes it easy to use curl in Google App Engine.
Thanks for the lib.

Noticed an issue :
On the original curl, the CURLINFO_HTTP_CODE does not return a string, but rather an integer.

Because Purl returns a string (example : http_code = "200" instead of http_code = 200), several other libraries that use curl, when "adapted" to work with Purl fail when testing for the http code.

Just wanted to let you know, so you could fix it.

Regards!