systemd: remove unused services
systemd: add a tmux-server service, run other tmuxs after this one
systemd: oneshot services should remain after exit
systemd: dropbox has no tray icon now
systemd: rename xmonad service
systemd: window manager target activates graphical and non-graphical targets
systemd: xbacklight service to change brightness on boot
systemd: rename pylab services, launch backend in non-graphical target
systemd: always restart mpd
systemd: graphical target goes after window-manager target
systemd: rename hack-terminal service to hacker-terminal
systemd: launch ncmpcpp on hacker terminal
script: to poll systemd target status