Non-numeric values should be enclosed within CDATA sections
Use default value for CURLOPT_SSL_VERIFYPEER. See http://snippets.webaware.com.au/howto/stop-turning-off-curlopt_ssl_verifypeer-and-fix-your-php-config/
Remove CURLOPT_USERPWD
Merge pull request #1 from pedrofaustino/small-improvements

Small improvements, thanks @pedrofaustino