YANG uses and UT

Change-Id: Id3ec5cfed2b8e2a7d2d580786c70b5804f03ecfa
diff --git a/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ListListener.java b/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ListListener.java
index a6c5496..42326b7 100644
--- a/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ListListener.java
+++ b/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ListListener.java
@@ -19,6 +19,7 @@
 import org.onosproject.yangutils.datamodel.YangAugment;
 import org.onosproject.yangutils.datamodel.YangCase;
 import org.onosproject.yangutils.datamodel.YangContainer;
+import org.onosproject.yangutils.datamodel.YangGrouping;
 import org.onosproject.yangutils.datamodel.YangInput;
 import org.onosproject.yangutils.datamodel.YangList;
 import org.onosproject.yangutils.datamodel.YangModule;
@@ -140,7 +141,7 @@
         if (curData instanceof YangModule || curData instanceof YangContainer
                 || curData instanceof YangList || curData instanceof YangCase
                 || curData instanceof YangNotification || curData instanceof YangInput
-                || curData instanceof YangOutput || curData instanceof YangAugment) {
+                || curData instanceof YangOutput || curData instanceof YangAugment || curData instanceof YangGrouping) {
             curNode = (YangNode) curData;
             try {
                 curNode.addChild(yangList);