Add keymap component

Adding a new keymap component that will
indicate the current keyboard layout (language)
and variant if any was set. I use the
standard X11 XKB APIs to retrieve and parse
the xkb_symbols set with setxkbmap.

Makefile

@@ -16,6 +16,7 @@ COM =\
 	components/ip\
 	components/kernel_release\
 	components/keyboard_indicators\
+	components/keymap\
 	components/load_avg\
 	components/netspeeds\
 	components/num_files\