[ONOS-4351][ONOS-4524] Augment linking and defect fixed.

Change-Id: I7c8e8c90579eea4631e014c4906a543a3c249427
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java
index b28bc66..278c332 100644
--- a/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java
@@ -242,6 +242,21 @@
     public static final String SPACE = " ";
 
     /**
+     * Static attribute for ListenerRegistry.
+     */
+    public static final String LISTENER_REG = "ListenerRegistry";
+
+    /**
+     * Static attribute for ListenerService.
+     */
+    public static final String LISTENER_SERVICE = "ListenerService";
+
+    /**
+     * Static attribute for listener package.
+     */
+    public static final String LISTENER_PKG = "org.onosproject.event";
+
+    /**
      * Static attribute for input string.
      */
     public static final String INPUT = "input";
@@ -862,14 +877,15 @@
     public static final String JAVA_UTIL_OBJECTS_IMPORT_CLASS = "Objects;\n";
 
     /**
-     * Static attribute for HasAugmentation class import package.
+     * Static attribute for AugmentationHolder class import package.
      */
-    public static final String HAS_AUGMENTATION_CLASS_IMPORT_PKG = "org.onosproject.yangutils.translator.tojava";
+    public static final String PROVIDED_AUGMENTATION_CLASS_IMPORT_PKG =
+            "org.onosproject.yangutils.translator.tojava";
 
     /**
-     * Static attribute for HasAugmentation class import class.
+     * Static attribute for AugmentationHolder class import class.
      */
-    public static final String HAS_AUGMENTATION_CLASS_IMPORT_CLASS = "HasAugmentation;\n";
+    public static final String AUGMENTATION_HOLDER_CLASS_IMPORT_CLASS = "AugmentationHolder;\n";
 
     /**
      * Static attribute for AugmentedInfo class import package.
@@ -887,9 +903,9 @@
     public static final String AUGMENTATION = "Augmentation";
 
     /**
-     * Static attribute for HasAugmentation class.
+     * Static attribute for AugmentationHolder class.
      */
-    public static final String HAS_AUGMENTATION = "HasAugmentation";
+    public static final String AUGMENTATION_HOLDER = "AugmentationHolder";
 
     /**
      * Static attribute for AugmentedInfo class.
@@ -897,6 +913,10 @@
     public static final String AUGMENTED_INFO = "AugmentedInfo";
 
     /**
+     * Static attribute for augmentable.
+     */
+    public static final String AUGMENTABLE = "Augmentable";
+    /**
      * Static attribute for list.
      */
     public static final String LIST = "List";