make leftmost child default for ChildSelector if field not present

Change-Id: I4ae92c31a39bc70606a3cbfc1d904a8b39f23d8e
diff --git a/changelog.rst b/changelog.rst
index 1f5dd27..871d7d1 100644
--- a/changelog.rst
+++ b/changelog.rst
@@ -9,6 +9,7 @@
 - **Interest**
 
   + Add specification of Link and SelectedDelegation fields
+  + Add default of leftmost child if ChildSelector field not present
 
 - **Data**