Update links to legal references
Summary:
Guide des citations, reférences et abréviations juridiques
Same than in 5b7113ef3a81, but pointing this time to UNamur web site,
as it doesn't seem to be available on the new Kluwers website.
Copyright Term and the Public Domain in the United States
The Cornell University Library updated site structure.
Test Plan: Check new URL
Reviewers: dereckson
Reviewed By: dereckson
Differential Revision: https://devcentral.nasqueron.org/D2564