keyboard: simplify configuration

xmodmap seems to modify the layout and will be kept if we switch to
another layout. Therefore, we only need to call it on start. Just move
the keyboard configuration to `start.lua`. `keyboard.lua` is just here
to manage kbdd.

rc/keyboard.lua

@@ -2,29 +2,6 @@
 
 local icons = loadrc("icons", "vbe/icons")
 
--- Global configuration
-if config.hostname == "guybrush" then
-   os.execute("setxkbmap us,fr '' compose:rctrl ctrl:nocaps")
-else
-   os.execute("setxkbmap us,fr '' compose:rwin ctrl:nocaps")
-end
-
--- Additional mappings
-local mappings = { Pause = "XF86ScreenSaver" }
-if config.hostname == "guybrush" then
-   mappings = { XF86AudioPlay = "XF86ScreenSaver" }
-end
-
-
-
-local function update_mappings()
-   for src, dst in pairs(mappings) do
-      os.execute(string.format("xmodmap -e 'keysym %s = %s'", src, dst))
-   end
-end
-
-update_mappings()
-
 local qdbus = {
    check = "qdbus ru.gentoo.KbddService /ru/gentoo/KbddService",
    next  = "qdbus ru.gentoo.KbddService /ru/gentoo/KbddService ru.gentoo.kbdd.next_layout"
@@ -38,13 +15,14 @@ dbus.add_signal("ru.gentoo.kbdd",
 		function(...)
 		   local data = {...}
 		   local layout = data[2]
-		   update_mappings()
+		   local screen = mouse.screen
+		   if client.focus then screen = client.focus.screen end
 		   nid = naughty.notify({ title = "Keyboard layout changed",
 					  text = "New layout is <i>" .. layout .. "</i>",
 					  replaces_id = nid,
 					  icon = icons.lookup({ name = "keyboard",
 								type = "devices" }),
-					  screen = client.focus.screen }).id
+					  screen = screen }).id
 		end)
 
 config.keys.global = awful.util.table.join(