Update changes

Author: MisterDA

CHANGES.md

@@ -7,6 +7,8 @@ unreleased
     - Stop unnecessarily forcing substitutions when initializing short-paths graph (#1988)
   + test suite
     - Add a test to ensure the behavior showed in issue #1517 is no longer relevant (#1995)
+  + frontend
+    - Fix a plethora of minor issues with the C code (#1998)
 
 merlin 5.6
 ==========