[master] add TCP pipelining support

4040.	[func]		Added server-side support for pipelined TCP
			queries. TCP connections are no longer closed after
			the first query received from a client. (The new
			"keep-response-order" option allows clients to be
			specified for which the old behavior will still be
			used.) [RT #37821]

bin/tests/system/pipelined/ns2/examplea.db

@@ -0,0 +1,35 @@
+; Copyright (C) 2014  Internet Systems Consortium, Inc. ("ISC")
+;
+; Permission to use, copy, modify, and/or distribute this software for any
+; purpose with or without fee is hereby granted, provided that the above
+; copyright notice and this permission notice appear in all copies.
+;
+; THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+; REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+; AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+; INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+; LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+; OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+; PERFORMANCE OF THIS SOFTWARE.
+
+$ORIGIN .
+$TTL 300	; 5 minutes
+examplea		IN SOA	mname1. . (
+				1          ; serial
+				20         ; refresh (20 seconds)
+				20         ; retry (20 seconds)
+				1814400    ; expire (3 weeks)
+				3600       ; minimum (1 hour)
+				)
+examplea.		NS	ns2.examplea.
+ns2.examplea.		A	10.53.0.2
+
+$ORIGIN examplea.
+a			A	10.0.1.1
+b			A	10.0.1.2
+c			A	10.0.1.3
+d			A	10.0.1.4
+e			A	10.0.1.5
+f			A	10.0.1.6
+g			A	10.0.1.7
+h			A	10.0.1.8