accounts-daemon service, fix gnome-shell, add libgnomekbd, musicbrainz5, sushi, gnome-contacts

For some reason, gnome-shell worked out without gnome-settings-daemon gschemas on my system. After a garbage collect + rebuild, it didn't work anymore. Turned out it was missing gschemas dependency.
The accounts-daemon is used for knowing some user information in gnome-shell, however we should forbid  changing accounts from `gnome-control-center user-accounts`.