YANG Grouping Linker Support

Change-Id: I2fec0c0bb4d1584e82ffba3228106897ccad2bf5
diff --git a/src/test/resources/SelfFileLinkingWithTypeWithSelfAndExternalPrefixMix.yang b/src/test/resources/SelfFileLinkingWithTypeWithSelfAndExternalPrefixMix.yang
index 038c7de..d5f346e 100644
--- a/src/test/resources/SelfFileLinkingWithTypeWithSelfAndExternalPrefixMix.yang
+++ b/src/test/resources/SelfFileLinkingWithTypeWithSelfAndExternalPrefixMix.yang
@@ -2,6 +2,9 @@
     yang-version 1;
     namespace http://huawei.com;
     prefix Ant;
+    import ietf-yang-types {
+             prefix "P";
+         }
     typedef Percentage {
     type int32;
     }