Update changes

Author: MisterDA

CHANGES.md

@@ -8,6 +8,8 @@ unreleased
   + test suite
     - Add a test to ensure the behavior showed in issue #1517 is no longer relevant (#1995)
     - Add a test to ensure the code fragment exhibited in issue #1118 no longer makes Merlin crash (#1996)
+  + frontend
+    - Fix a plethora of minor issues with the C code (#1998)
 
 merlin 5.6
 ==========