#17729: remove the outdated Advocacy HOWTO, as suggested by the author.
#17729: merge with 3.3.
#17729: remove the Advocacy HOWTO from the index.
#17729: merge with 3.3.
Ensure that plistlib doesn't corrupt deeply nested datastructures

Without this changeset plistlib would write empty tags for plistlib.Data
objects in deeply nested datastructures.

Fixes #17353
(3.3->default) Ensure that plistlib doesn't corrupt deeply nested datastructures

Without this changeset plistlib would write empty tags for plistlib.Data
objects in deeply nested datastructures.

Fixes #17353