Add update-lang-cache script.

This script can be used, to update the language cache if any strings will be added
or modified.

config/rootfiles/common/stage2

@@ -75,6 +75,7 @@ usr/local/bin/setddns.pl
 usr/local/bin/settime
 usr/local/bin/timecheck
 #usr/local/bin/uname
+usr/local/bin/update-lang-cache
 usr/local/bin/vpn-watch
 #usr/local/include
 #usr/local/lib

src/scripts/update-lang-cache

@@ -0,0 +1,3 @@
+#!/bin/sh
+perl -e "require '//var/ipfire/lang.pl'; &Lang::BuildCacheLang"
+