Add new attributes to default namespace (#1104)

Otherwise they will nbot be fetched from the metadata reliably

Completes 9d0b2fc4  (#832)

thunarx/thunarx-file-info.h

@@ -52,6 +52,7 @@ G_BEGIN_DECLS
   "metadata::thunar-view-type," \
   "metadata::thunar-sort-column,metadata::thunar-sort-order," \
   "metadata::thunar-zoom-level," \
+  "metadata::thunar-zoom-level-ThunarDetailsView,metadata::thunar-zoom-level-ThunarIconView,metadata::thunar-zoom-level-ThunarCompactView," \
   "metadata::thunar-highlight-color-background,metadata::thunar-highlight-color-foreground" \