Add start of IPv6 implementation. Currently most of this is avoiding
IPv6 in winbindd, but moves most of the socket functions that were
wrongly in lib/util.c into lib/util_sock.c and provides generic
IPv4/6 independent versions of most things. Still lots of work
to do, but now I can see how I'll fix the access check code.
Nasty part that remains is the name resolution code which is
used to returning arrays of in_addr structs.
Jeremy.
(This used to be commit
3f6bd0e1ec5cc6670f3d08f76fc2cd94c9cd1a08)