Add note on inbox specs when accepted or rejected

[Ppjet6]

I often find myself looking at things in the Inbox I don't know what their current state is.

It would be great if there was a note on the document saying where I can find it if it's been accepted, or if it's been rejected, i.e., "This now lives at xep-XXXX." or "This has been rejected, see <thread>."

@horazont says:

you need to:

• draft a format how to put that into the protoxep xml file
• modify the dtd to allow it
• modify the xsl to use it