Add missing translations of "Building section"

mods/arrow_signs/locale/de.txt

@@ -25,3 +25,4 @@ The Good-Bye Room = Der Abschiedsraum
 Exit = Ausgang
 Comestibles room = Lebensmittelraum
 Smelting room = Verhüttungsraum
+Building section = Bauabschnitt

mods/arrow_signs/locale/el.txt

@@ -25,3 +25,4 @@ The Good-Bye Room = Δωμάτιο αποχαιρετισμού
 Exit = Έξοδος
 Comestibles room = Δωμάτιο φαγητών
 Smelting room = Δωμάτιο λιωσίματος
+Building section = Περιοχή κτισίματος

mods/arrow_signs/locale/es.txt

@@ -25,3 +25,4 @@ The Good-Bye Room = Sala de despedida
 Exit = Salida
 Comestibles room = Sala de comestibles
 Smelting room = Sala de fundición
+Building section = Sección de construcción

mods/arrow_signs/locale/it.txt

@@ -25,3 +25,4 @@ The Good-Bye Room = Stanza di Addio
 Exit = Uscita
 Comestibles room = Stanza alimenti
 Smelting room = Stanza fusione
+Building section = Sezione costruire

mods/arrow_signs/locale/nl.txt

@@ -25,3 +25,4 @@ The Good-Bye Room = De Afscheidskamer
 Exit = Uitgang
 Comestibles room = Voedingskamer
 Smelting room = Smeltingkamer
+Building section = Afdeling Bouwen

mods/arrow_signs/locale/template.txt

@@ -25,3 +25,4 @@ The Good-Bye Room
 Exit
 Comestibles room
 Smelting room
+Building section