New core and delegation drafts uploaded

All,

I have uploaded xacml core 3.0 wd 4 and delegation wd 18.

These fix some typos, update the examples to the new xpath datatype and 
changes disjunctive/conjunctive matches to anyof/allof.

So there are not many changes, but I am uploading them anyway since I 
intend to update the document templates as the next step. It's cleaner 
and easier to follow the changes if I don't change the technical content 
while I do that, hence the small update now.

Regards,
Erik