awful.key({ modkey,           }, "Return", function () awful.util.spawn(terminal) end),
    awful.key({ modkey,           }, "BackSpace", function() awful.util.spawn("thunar") end),
    awful.key({                   }, "Print", function() awful.util.spawn("xfce4-screenshooter") end),
    awful.key({ modkey,           }, "s", function() awful.util.spawn("xfce4-settings-manager") end),