Add changelog entry

Author: Leonidas-from-XIV

CHANGES.md

@@ -9,6 +9,8 @@
 #### Fixed
 
 - Fixed compatibility with Cmdliner 1.1.0 (#371, @Leonidas-from-XIV)
+- Report errors and exit codes of toplevel directives (#382, @talex5,
+  @Leonidas-from-XIV)
 
 #### Removed