Improve handling of unknown header types

Change-Id: I5c1f0d12c9dcb11421745c0ca55865e4efc388db
diff --git a/Changes b/Changes
index f30ae16..c2efa8d 100644
--- a/Changes
+++ b/Changes
@@ -10,6 +10,7 @@
         - Deprecate KORAPXMLTEI_INLINE environment variable
           in favor of --skip-inline-token-annotations
         - Improve script handling of broken data
+        - Improve handling of unknown header types
 
 1.00 2021-02-18 Release
         - -s option added that uses sentence boundaries