ui: Added on-screen search feature (issue #79)

* Use menu action "Edit -> Find in View" or Ctrl + D
* UI displayed as search bar at bottom of main window
* Hide search bar with ECS or close button
* Entering a query searches in name of graph nodes and code contents of code view
* Use Enter to iterate through matches, well move match into view in graph and code view
* Checkboxes allow for adding/removing results for certain views
* Create Bookmark shortcut is now CTRL + S

bug id = 79

src/lib_gui/qt/element/QtCodeNavigator.h

@@ -83,6 +83,11 @@ public:
 
 	void refreshStyle();
 
+	size_t findScreenMatches(const std::string& query);
+	void activateScreenMatch(size_t matchIndex);
+	void deactivateScreenMatch(size_t matchIndex);
+	void clearScreenMatches();
+
 	void scrollToValue(int value, bool inListMode);
 	void scrollToLine(const FilePath& filePath, unsigned int line);
 	void scrollToDefinition(bool animated, bool ignoreActiveReference);
@@ -192,6 +197,9 @@ private:
 
 	ScrollRequest m_scrollRequest;
 	bool m_singleHasNewFile;
+
+	std::vector<std::pair<QtCodeArea*, Id>> m_screenMatches;
+	Id m_activeScreenMatchId = 0;
 };
 
 #endif // QT_CODE_NAVIGATOR_H