one additional attribute

Hi, 
 Some of you might be following my bits of strife with speeding up the
importing of the metadata using python and libxml2.

I've gotten the code to a point using the xmlReader interface to libxml2
- ran into a snag of having no way to produce an intelligent progress
callback for feeding back into an interface to give the user some
estimate of when it would be done.

so I'm wondering if everyone thinks it would be ok to add a total
packages counter attribute to the first tag in the metadata ie:

primary.xml:
<metadata packagecount="1610">

filelists.xml:
<filelists packagecount="1610">

otherdata.xml:
<otherdata packagecount="1610">

it shouldn't disrupt any other parsers but it would mean nicer progress
callbacks for those folks who will hopefully use the importing routines
in python.

Does this sound ok?

Thanks
-sv