RE: [xml-dev] next step for 23309 et al

I've just checked in fixes to make my stuff pass the i18n script, as well as mods to the documentation to cover node pre-expansion level and tree editor syntax completion.

My UI impact was actually quite minimal.  I didn't add any new dialogs or components, so I'm not sure if there's really any a11y or UI checklist concerns.  I took a quick look through the a11y faq and the UI checklist, but I couldn't think of anything offhand.

The UI impacts are:
propertysheet in tree/nodes/propertysheet
The add submenu of the ElementNode's context menu

> Regarding tree customizations doc I'm uncertain. It's a kind
> of declarative API. I still consider it experimental as there
> is a room for enhancements that may break backward compatibility.

agreed.

Rich