[Rpm-metadata] xml update

[seth vidal]

> 
> I can/will make this data magically (and configurably) appear from
> existing apt-rpm files using a header extension. From an rpm-python
> point of view, this is just another tag, so common metadata can
> be entirely automated, streamlining maintenance.

fine - that doesn't matter to me all that much - my concern is we have
packages right here today that need this. I'd like to have this metadata
defined - at least for ver 1 before FC2 is released.


> Yes, existence must be optional, with well defined default value if/when 
> missing,
> and permission to totally ignore the value until reliable 
> implementations exist.


great. Then let's start listing mandatory and optional 'common' fields
and defining this specification more.

-sv