Allow incomplete downloads to be resumed even when server rejects HEAD requests #5421
Use GET rather than HEAD when checking for range support in curl_download.
Although, honestly I don't understand what was wrong with the behavior before 0721271 where curl_download always tried
…load. * Some HTTP servers apparently support ranges but don't support HEAD. * This is a more realistic check anyway since the actual download request will use GET (not HEAD). * This fixes #5420.