logic: rewrote messages handling token activation for correct restoring on undo

* saving search query to undo stack with MessageSearch
* saving node and edge with name to undo stack with MessageActivateNode and MessageActivateEdge
* added FeatureController that handels distribution of MessageActivateTokens
* clearing views when refreshing or changing project
* clearing undo stack when changing project
* added StorageCache derived from StorageAccessProxy

src/lib/data/search/SearchMatch.h

@@ -16,6 +16,7 @@ struct SearchMatch
 	static void log(const std::vector<SearchMatch>& matches, const std::string& query);
 	static std::deque<SearchMatch> stringDequeToSearchMatchDeque(const std::deque<std::string>& deque);
 	static std::deque<std::string> searchMatchDequeToStringDeque(const std::deque<SearchMatch>& deque);
+	static std::string searchMatchDequeToString(const std::deque<SearchMatch>& deque);
 
 	SearchMatch();
 	SearchMatch(const std::string& query);