Properly handle being redirected to an FTP URL.
Properly handle being redirected to an FTP URL.

Also fix a couple of not-so-minor bugs:
 - missing case for HTTP_SEE_OTHER
 - incorrect definition of HTTP_NEED_PROXY_AUTH

PR:		20259
MFC after:	2 weeks

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase