Modified warden to create borrowed cells on-demand and to scrap returned ones.

Change-Id: If32a0da18ff9d4c05645017e5cc7481bbd1ab0cd
diff --git a/tools/test/bin/onos-verify-cell b/tools/test/bin/onos-verify-cell
index 4b3a0ee..ec34cab 100755
--- a/tools/test/bin/onos-verify-cell
+++ b/tools/test/bin/onos-verify-cell
@@ -6,6 +6,6 @@
 [ ! -d "$ONOS_ROOT" ] && echo "ONOS_ROOT is not defined" >&2 && exit 1
 . $ONOS_ROOT/tools/build/envDefaults
 
-for node in $(env | sort | egrep "OC[0-9N]+" | cut -d= -f2); do
-    printf "%s: " $node; ssh -n -o PasswordAuthentication=no $ONOS_USER@$node date
+for node in $OCN $(env | sort | egrep "OC[0-9]+" | cut -d= -f2); do
+    printf "%s: " $node; ssh -n -o StrictHostKeyChecking=no -o PasswordAuthentication=no $ONOS_USER@$node hostname
 done