Update changelog

Author: timfel

CHANGELOG.md

@@ -7,6 +7,8 @@ language runtime. The main focus is on user-observable behavior of the engine.
 
 * Added subclassing of Java classes in JVM mode
 * Use native posix functions in the GraalPython Launcher
+* Support iterating over Python objects from Java and other languages as well as iterating over foreign objects in Python
+* Support catching foreign exceptions in catch-all except clauses
 
 ## Version 21.1.0