Comments In Introspection XML?

[Lawrence D'Oliveiro]

I think it would be handy to be able to include explanatory comments in
the introspection XML. This would be helpful to scripters trying to
figure out how to communicate with some D-Bus peer; the comments can
explain what the methods/signals/properties are for, rather than having
to try to guess what they do from their names or other clues.

I can think of two options for doing this:
  * use XML comments
  * or, add a new <annotation> type.

A slight drawback with the first one is that some XML parsers strip out
comments.

Thoughts?