Back out r42188 for now "* Disable this entirely unless curl is available so we don...

Back out r42188 for now "* Disable this entirely unless curl is available so we don't blow up. Needs a-fixin
* Move the curl calls to http::request() so we can at least start to make this work for the file_get_contents() fallback"

Sticking CURL-specific options in the Http::get call seems unwise as that ties you to a specific backend, assuming Http::get won't change. Further, it seems that if it does use the backend, it just plain won't work -- the returned data will be thrown away instead of saved to the target file.