Add separators in Dutch noun templates
The Dutch noun templates currently display the main forms in the left column and diminutive forms in the right column. Adding separators will cause the singular forms to be in the left column and plural forms to be in the right column, matching the Dutch Wiktionary [1]. This is also more consistent with the German templates (as a neighbouring and closely related language, it would not be surprising if a Dutch speaker also wants to edit German). The tab order will not be affected.