[xacml] Web site update

Colleagues,

I updated the Web site. I created Schema subcommittee page and the time for
the SC conf call, Monday 10AM US Eastern time. I want to make sure that is
agreed or not. I also added a link to the article that refers to our work.
Please let me know any corrections and additions.

Best
Michiharu Kudo

IBM Tokyo Research Laboratory, Internet Technology
Tel. +81 (46) 215-4642   Fax +81 (46) 273-7428