updating the plan

tat_requirements/plan.md

@@ -78,7 +78,7 @@ Code we write<a name="code-we-write"></a>
 - coding style, class template (architect Robbie)
 
 
-## Controlled vocabularies and tag system [tag-system]
+## Controlled vocabularies and tag system <a name="tag-system"></a>
 
 
 The tags are very similar to vocabulary entryies in that the tag values are controlled. The difference being a