Fixed text of exception

Author: PetrPytelka

src/main/java/com/scriptbasic/utility/functions/UtilityFunctions.java

@@ -149,15 +149,15 @@ public static Long length(final Object arg) {
     @BasicFunction(classification = Utility.class)
     public static Double cdbl(final Object arg) throws BasicRuntimeException {
         if (arg == null) {
-            throw new BasicRuntimeException("NULL cannot be converted to double");
+            throw new BasicRuntimeException("undef cannot be converted to double");
         }
         return BasicDoubleValue.asDouble(RightValueUtility.createRightValue(arg));
     }
 
     @BasicFunction(classification = Utility.class)
     static public Long clng(final Object arg) throws BasicRuntimeException {
         if (arg == null) {
-            throw new BasicRuntimeException("NULL cannot be converted to long");
+            throw new BasicRuntimeException("undef cannot be converted to long");
         }
         return BasicLongValue.asLong(RightValueUtility.createRightValue(arg));
     }