Reformat debian/copyright to conform to draft DEP5 rev. 135. Add GPL disclaimers. Adjust years for debian/*.
Reformat debian/copyright to conform to draft DEP5 rev. 135. Add GPL disclaimers. Adjust years for debian/*.

tchx84/debian-pkg-sugar-artwork,tchx84/debian-pkg-sugar-artwork,tchx84/debian-pkg-sugar-artwork