Sometimes, you want to fetch a file in memory so you can
store it on multiple places on disk whitout having to download it
again or copy files. while http_fetch_page works for fetching data
in memory, the possible filename found in the 'Content-Disposition'
header-feild is not accounted to.
http_fetch_file() fetches the data and store it in memory while trying to
get ahold of the filename.
