Make XMLEditor.add_object_to_list return the element added.

Fix bugs in remove_object_from_list, add_package.
Add promotion ability to jss_helper.

Policy renaming very fragile and specific to our organization.
Update CHANGELOG.
Fix update method not replacing instance's data. Add ability to replace all data with a template. Add list_type=script to scripts.
Pylint. Added python-mode to vim, so ignore .ropeproject.
Removed jss_helper.
Changelog edit.
Set release date.