Disable Kerberos auth.  BZ 769254
Disable Kerberos auth.  BZ 769254

When a proxy supports NEGOTIATE auth scheme but there's
no valid kerberos ticket, Curl won't use Basic or NTLM,
although these would succeed.

Distrotech/urlgrabber,tradej/urlgrabber,oe-lite/urlgrabber,Distrotech/urlgrabber,tradej/urlgrabber,henrysher/urlgrabber,tradej/urlgrabber,henrysher/urlgrabber,henrysher/urlgrabber,Distrotech/urlgrabber,oe-lite/urlgrabber,oe-lite/urlgrabber,oe-lite/urlgrabber,henrysher/urlgrabber,Distrotech/urlgrabber