Add license property and field.

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/apps/thematic/trunk@36780 72102866-910b-0410-8b05-ffd578937521
set delegate of new field

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/apps/thematic/trunk@36787 72102866-910b-0410-8b05-ffd578937521