[ONOS-4411,ONOS-4413,ONOS-4526] Yang Enumeration Translator and Defect fixes.

Change-Id: Ie5b6b5d6d6df283a57ae06b1979f0d03022f3baf
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 965367c..dc7920a 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
@@ -41,7 +41,6 @@
     public static final String INTERFACE_JAVA_DOC = " * Abstraction of an entity which represents the"
             + " functionality of ";
 
-
     /**
      * JavaDocs for event.
      */
@@ -52,7 +51,6 @@
      */
     public static final String EVENT_LISTENER_JAVA_DOC = " * Abstraction for event listener of ";
 
-
     /**
      * JavaDocs for builder interface class.
      */
@@ -169,6 +167,11 @@
     public static final String NEW_LINE = "\n";
 
     /**
+     * Static attribute for default.
+     */
+    public static final String DEFAULT = "default";
+
+    /**
      * Static attribute for multiple new line.
      */
     public static final String MULTIPLE_NEW_LINE = "\n\n";
@@ -434,6 +437,16 @@
     public static final String CLEAR = "clear";
 
     /**
+     * Static attribute for switch syntax.
+     */
+    public static final String SWITCH = "switch";
+
+    /**
+     * Static attribute for case syntax.
+     */
+    public static final String CASE = "case";
+
+    /**
      * Static attribute for temp val syntax.
      */
     public static final String TMP_VAL = "tmpVal";
@@ -703,7 +716,6 @@
      */
     public static final String SERVICE = "Service";
 
-
     /**
      * Static attribute for interface syntax.
      */
@@ -875,7 +887,7 @@
     public static final String ARRAY_LIST = "ArrayList";
 
     /**
-     * comment to be added for autogenerated impl methods.
+     * Comment to be added for autogenerated impl methods.
      */
     public static final String YANG_UTILS_TODO = "//TODO: YANG utils generated code";