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/QtCodeNavigateable.h

@@ -10,6 +10,7 @@
 class FilePath;
 class QRectF;
 class QAbstractScrollArea;
+class QtCodeArea;
 class QWidget;
 
 class QtCodeNavigateable
@@ -29,6 +30,8 @@ public:
 
 	virtual void onWindowFocus() = 0;
 
+	virtual void findScreenMatches(const std::string& query, std::vector<std::pair<QtCodeArea*, Id>>* screenMatches) = 0;
+
 protected:
 	void ensureWidgetVisibleAnimated(QWidget* parentWidget, QWidget *childWidget, QRectF rect, bool animated, bool onTop);
 	void ensurePercentVisibleAnimated(double percentA, double percentB, bool animated, bool onTop);