network/nfs01: add IPv6 test-cases

* cleanup test, apply test_net.sh library
* don't use loop for test binaries because there is only one
  right now, 'open_files'
* use tst_tmpdir()
* update test-cases in runtest, add NFS over IPv6
* make four test-cases with NFS v3 and v4.

Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Cyril Hrubis <chrubis@suse.cz>
diff --git a/runtest/nfs b/runtest/nfs
index 19f2344..7bee16f 100644
--- a/runtest/nfs
+++ b/runtest/nfs
@@ -2,7 +2,11 @@
 #
 # PLEASE READ THE README FILE IN /nfs BEFORE RUNNING THESE.
 #
-nfs01 export VERSION SOCKET_TYPE; TCbin=$LTPROOT/testcases/bin nfs01
+nfs3_01 export VERSION=3 SOCKET_TYPE=udp; nfs01
+nfs4_01 export VERSION=4 SOCKET_TYPE=tcp; nfs01
+nfs3_ipv6_01 export VERSION=3 SOCKET_TYPE=udp; nfs01 -6
+nfs4_ipv6_01 export VERSION=4 SOCKET_TYPE=tcp; nfs01 -6
+
 nfs02 export VERSION SOCKET_TYPE; TCbin=$LTPROOT/testcases/bin nfs02
 nfs03 export VERSION SOCKET_TYPE; TCbin=$LTPROOT/testcases/bin nfs03
 nfs04 export VERSION SOCKET_TYPE; TCbin=$LTPROOT/testcases/bin nfs04