add missing file to POTFILES
add missing file to POTFILES


(Old svn revision: 3447)

dnschneid/xfce4-genmon-plugin,xfce-mirror/xfce4-genmon-plugin,tonypaulic/xfce4-genmon-plugin,dnschneid/xfce4-genmon-plugin,xfce-mirror/xfce4-genmon-plugin,xfce-mirror/xfce4-genmon-plugin,dnschneid/xfce4-genmon-plugin,tonypaulic/xfce4-genmon-plugin,tonypaulic/xfce4-genmon-plugin