src: remove unused stuff

* PersistenStorage::removeUnusedNames
* Dictionary
* DictionaryTestSuite

src/lib/data/TaskCleanStorage.cpp

@@ -34,7 +34,7 @@ Task::TaskState TaskCleanStorage::update()
 	if (m_fileCount)
 	{
 		MessageStatus("Cleaning up names (ESC to quit)", false, true).dispatch();
-		m_storage->removeUnusedNames();
+		m_storage->clearCaches();
 	}
 
 	return Task::STATE_FINISHED;