Added filename params to download in case filename could not be parsed from URL

Sometimes URLs for images looks like this (real example):
http://www.klops.ru:80/getphoto.php?s=lbox4&f=a023613a0ba9be6b525cc4a015
05cb26.jpg

And carrierwave now parses filename as getphoto.php which will fail
whitelist extension validation. So we need an ability to pass filename
to remote_url