Fix changing tilesets not marking layouts as unsaved

include/core/maplayout.h

@@ -25,6 +25,7 @@ public:
 
 
     bool loaded = false;
+    bool hasUnsavedDataChanges = false;
 
     QString id;
     QString name;

include/mainwindow.h

@@ -200,6 +200,7 @@ private slots:
     void applyUserShortcuts();
     void markMapEdited();
     void markSpecificMapEdited(Map*);
+    void markLayoutEdited();
 
     void on_actionNew_Tileset_triggered();
     void on_action_Save_triggered();