Speed up tag local cache

boards/models/tag.py

@@ -133,7 +133,7 b' class Tag(models.Model, Viewable):'
         return self.required
 
     def _get_locale_cache_key(self):
-        return '{}_{}'.format(self.id, get_language())
+        return [get_language()]
 
     @cached_result(key_method=_get_locale_cache_key)
     def get_localized_name(self):