Fix the unexpected.tdb database problem. Change nmbd to store the

Fix the unexpected.tdb database problem. Change nmbd to store the
transaction id of packets it was requested to send via a client, and
only store replies that match these ids. On the client side change
clients to always attempt to ask nmbd first for name_query and
node_status calls, and then fall back to doing socket calls if
we can't talk to nmbd (either nmbd is not running, or we're not
root and cannot open the messaging tdb's). Fix readers of unexpected.tdb
to delete packets they've successfully read.

This should fix a long standing problem of unexpected.tdb
growing out of control in noisy NetBIOS envioronments with
lots of bradcasts, yet still allow unprivileged client apps
to work mostly as well as they already did (nmblookup for
example) in an environment when nmbd isn't running.

Jeremy.

Autobuild-User: Jeremy Allison <jra@samba.org>
Autobuild-Date: Sun Nov 14 05:22:45 UTC 2010 on sn-devel-104