Properly handle tag without aliases (though don't know how this can happen)

boards/models/tag.py

@@ -89,7 +89,17 b' class Tag(models.Model, Viewable):'
                                blank=True, related_name='children')
 
     def get_name(self):
-        return self.aliases.get(locale=DEFAULT_LOCALE).name
+        try:
+            alias = self.aliases.get(locale=DEFAULT_LOCALE)
+        except TagAlias.DoesNotExist:
+            alias = self.aliases.first()
+
+        if alias:
+            return alias.name
+        else:
+            # This is an extremely bad situation, somehow we have a tag without
+            # any alias
+            return 'BROKEN #{}'.format(self.id)
 
     def __str__(self):
         return self.get_name()