[ONOS-4753] Identity/identityref implementation and UT

Change-Id: I40148fa228465555be3bdf410cc294ffc0f34c18
diff --git a/utils/yangutils/plugin/src/test/resources/interfileidentityincludedependencyUndefined/featurefile2.yang b/utils/yangutils/plugin/src/test/resources/interfileidentityincludedependencyUndefined/featurefile2.yang
new file mode 100644
index 0000000..14fd83c
--- /dev/null
+++ b/utils/yangutils/plugin/src/test/resources/interfileidentityincludedependencyUndefined/featurefile2.yang
@@ -0,0 +1,19 @@
+submodule syslog2 {
+     yang-version 1;
+     belongs-to "syslog1" {
+         prefix "sys1";
+     }
+
+     import "syslog3" {
+        prefix "sys3";
+     }
+
+     identity tunnel-type {
+         base sys3:final-address-family;
+     }
+
+     identity ref-address-family {
+         base sys3:final-address-family;
+     }
+}
+