`org-clock-clocktable-language-setup': add dutch strings.

* lisp/org-clock.el (org-clock-clocktable-language-setup): Add list of
dutch strings.

lisp/org-clock.el

@@ -260,7 +260,8 @@ For more information, see `org-clocktable-write-default'."
 
 (defcustom org-clock-clocktable-language-setup
   '(("en" "File"     "L"  "Timestamp"  "Headline" "Time"  "ALL"  "Total time" "File time")
-    ("fr" "Fichier"  "N"  "Horodatage" "Tâche"    "Durée" "TOUT" "Durée totale" "Durée fichier"))
+    ("fr" "Fichier"  "N"  "Horodatage" "Tâche"    "Durée" "TOUT" "Durée totale" "Durée fichier")
+    ("nl" "Bestand"  "N"  "Tijdstip"   "Taak"    "Duur"   "ALLES" "Totale duur" "Bestandstijd"))
   "Terms used in clocktable, translated to different languages."
   :group 'org-clocktable
   :type 'alist)