Add "Game" editor for better runtime debugging

scene/main/scene_tree.h

@@ -143,6 +143,7 @@ private:
 	bool debug_navigation_hint = false;
 #endif
 	bool paused = false;
+	bool suspended = false;
 
 	HashMap<StringName, Group> group_map;
 	bool _quit = false;
@@ -343,6 +344,8 @@ public:
 
 	void set_pause(bool p_enabled);
 	bool is_paused() const;
+	void set_suspend(bool p_enabled);
+	bool is_suspended() const;
 
 #ifdef DEBUG_ENABLED
 	void set_debug_collisions_hint(bool p_enabled);