YANG Grouping Linker Support

Change-Id: I2fec0c0bb4d1584e82ffba3228106897ccad2bf5
diff --git a/utils/yangutils/src/test/resources/ValidAugmentStatement.yang b/utils/yangutils/src/test/resources/ValidAugmentStatement.yang
index 59ebe67..6175c35 100644
--- a/utils/yangutils/src/test/resources/ValidAugmentStatement.yang
+++ b/utils/yangutils/src/test/resources/ValidAugmentStatement.yang
@@ -6,6 +6,9 @@
     import interface-module {
         prefix "if";
     }
+    import ietf-yang-types {
+             prefix "P";
+         }
     augment "/if:interfaces/if:ifEntry" {
         when "if:ifType='ds0'";
         leaf ds0ChannelNumber {