Meta tab shows wrong Topicmap information for implicitly hidden assocs
The Detail Panel's "Meta" tab is supposed to show only topicmaps where the topic/assoc is actually visible (= not hidden).
For implicitly hidden assocs the topicmaps are still shown. That's a bug.
Remember: an assoc is regarded implicitly hidden if the user hides one of its players. In contrast an assoc is regarded explicitly hidden if the user issues the Hide command on that assoc directly. For an explicitly hidden assoc its "Topicmap Context" assoc is deleted, for an implicitly hidden assoc it is not. See #100 (closed).