Don't set up the soup-transfer callbacks to keep reading off the

Don't set up the soup-transfer callbacks to keep reading off the

        * libsoup/soup-message.c (soup_message_cleanup): Don't set up the
        soup-transfer callbacks to keep reading off the connection unless
        we're actually going to keep the connection around afterward.
        Otherwise we can just close it.

        * libsoup/soup-transfer.c: Re-kludge the awful IGNORE_CANCEL
        thingy so that it's possible to cancel a read from inside a
        callback so that the above change actually works instead of just
        crashing.