Added hax's classy Byzantium logo backdrop.

Signed-off-by: The Doctor <drwho@virtadpt.net>
Added the custom icon files that go into usr/share/icons/byzantium/.

Signed-off-by: The Doctor <drwho@virtadpt.net>
Copied the "No sleep 'till Brooklyn!" background image that goes in
usr/share/wallpapers/ into this sub-module.

Signed-off-by: The Doctor <drwho@virtadpt.net>