add animation panel

src/node_panel_animation.h

@@ -0,0 +1,12 @@
+#include "node_border.h"
+
+class NodePanelAnimation : public NodeBorder
+{
+public:
+    using this_class = NodePanelAnimation;
+    using parent = NodeBorder;
+    virtual Node* clone_instantiate() const override;
+    virtual void clone_finalize(Node* dest) const override;
+    virtual void init() override;
+    void init_controls();
+};