Ditz issue update
Add a deep merge testcase, exercises key ordering
Merge branch 'test-case-deep-merge'
Don't run finalizer for Proxy in heap destruction
Test case for Proxy finalization on heap destruct
Release note: Proxy finalization fix
Merge branch 'bug-proxy-finalize-twice'

Fix bug for Proxy finalizer handling at heap destruction.  If a Proxy
was reachable and its target had a finalizer, the finalizer would get
executed both for the target and for the Proxy object.