CoreObject: Remove 'Author:' entires from the license headers, and rewrite the Copyright line to be the list of author names, rather than just one author as it was previously

git-svn-id: svn://svn.gna.org/svn/etoile/trunk/Etoile/Frameworks/CoreObject@9895 7b3f36aa-e6db-49c1-8b4c-66eac1997e64