Bug 261 Fix NSR member vnf index type for NS service primitive

Signed-off-by: Ravi Chamarty <ravi.chamarty@riftio.com>
(cherry picked from commit 8fa3ce93eb414b68b6bab32e00706a655c1ea7a1)

Change-Id: Ibc788f78002984ab64afc49fa21879ff6828f02f
diff --git a/models/plugins/yang/nsr.yang b/models/plugins/yang/nsr.yang
index 3fdd642..a3f9f57 100644
--- a/models/plugins/yang/nsr.yang
+++ b/models/plugins/yang/nsr.yang
@@ -855,7 +855,7 @@
             leaf member-vnf-index-ref {
               description
                  "Reference to member-vnf within constituent-vnfds";
-              type string;
+              type uint64;
             }
 
             leaf vnfd-id-ref {