Make named a singleton process [RT#37908]

Conflicts:
	bin/tests/system/conf.sh.in
	lib/dns/win32/libdns.def.in
	lib/isc/win32/file.c

The merge also needed to update files in legacy and tcp system tests
(newly introduced in master after branch was created) to introduce use
of lockfile.

bin/tests/system/database/clean.sh

@@ -18,3 +18,4 @@
 
 rm -f ns1/named.conf ns1/named.run ns1/named.memstats
 rm -f dig.out.*
+rm -f ns*/named.lock