Fixed wrong argument for datetimechooser widget

The argument for specifying the language of the DateTimeChooser is wrong, which makes it impossible to customise the language. Compare for reference the argument specification for the DateChooser and the TimeChooser :-)

CHANGELOG.txt

@@ -10,6 +10,7 @@ Changelog
  * Fix: Inline panel first and last sorting arrows correctly hidden in non-default tabs (Matt Westcott)
  * Fix: `WAGTAILAPI_LIMIT_MAX` now accepts None to disable limiting (jcronyn)
  * Fix: In PostgreSQL, new default ordering when ranking of objects is the same (Bertrand Bordage)
+ * Fix: Enabled translations within date-time chooser widget (Lucas Moeskops)
 
 
 1.12 LTS (21.08.2017)

docs/releases/1.13.rst

@@ -25,6 +25,7 @@ Bug fixes
  * Inline panel first and last sorting arrows correctly hidden in non-default tabs (Matt Westcott)
  * ``WAGTAILAPI_LIMIT_MAX`` now accepts None to disable limiting (jcronyn)
  * In PostgreSQL, new default ordering when ranking of objects is the same (Bertrand Bordage)
+ * Enabled translations within date-time chooser widget (Lucas Moeskops)
 
 
 Upgrade considerations

wagtail/wagtailadmin/static_src/wagtailadmin/js/page-editor.js

@@ -86,7 +86,7 @@ function initDateTimeChooser(id, opts) {
             i18n: {
                 lang: window.dateTimePickerTranslations
             },
-            language: 'lang',
+            lang: 'lang',
             onGenerate: hideCurrent
         }, opts || {}));
     } else {