YANG Grouping Linker Support

Change-Id: I2fec0c0bb4d1584e82ffba3228106897ccad2bf5
diff --git a/utils/yangutils/src/test/resources/SelfFileLinkingWithTypdefHierarchicalRefUnresolved.yang b/utils/yangutils/src/test/resources/SelfFileLinkingWithTypdefHierarchicalRefUnresolved.yang
index 35c28b6..a3e4379 100644
--- a/utils/yangutils/src/test/resources/SelfFileLinkingWithTypdefHierarchicalRefUnresolved.yang
+++ b/utils/yangutils/src/test/resources/SelfFileLinkingWithTypdefHierarchicalRefUnresolved.yang
@@ -2,6 +2,9 @@
     yang-version 1;
     namespace http://huawei.com;
     prefix Ant;
+    import ietf-yang-types {
+             prefix "P";
+         }
     typedef Percentage {
     type P:Per;
     }