YANG construct collision detection framework added

Change-Id: I1458f9e3192641f3f90c444798c31a64536ffa5d
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ReferenceListener.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ReferenceListener.java
index 6e83e86..aaca80c 100644
--- a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ReferenceListener.java
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/listeners/ReferenceListener.java
@@ -22,7 +22,7 @@
 import org.onosproject.yangutils.parser.exceptions.ParserException;
 import org.onosproject.yangutils.parser.impl.TreeWalkListener;
 
-import static org.onosproject.yangutils.parser.ParsableDataType.REFERENCE_DATA;
+import static org.onosproject.yangutils.utils.YangConstructType.REFERENCE_DATA;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorLocation.ENTRY;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorMessageConstruction.constructListenerErrorMessage;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorType.INVALID_HOLDER;
@@ -56,8 +56,8 @@
      * rule (reference), performs validation and updates the data model
      * tree.
      *
-     * @param listener listener's object.
-     * @param ctx context object of the grammar rule.
+     * @param listener listener's object
+     * @param ctx context object of the grammar rule
      */
     public static void processReferenceEntry(TreeWalkListener listener,
                                              GeneratedYangParser.ReferenceStatementContext ctx) {