Arc editor : use QPropertyUndoCommand instead of ChangePartCommand

git-svn-id: svn+ssh://svn.tuxfamily.org/svnroot/qet/qet/trunk@4066 bfdf4180-ca20-0410-9c96-a3a8aa849046

sources/editor/graphicspart/abstractpartellipse.h

@@ -49,6 +49,11 @@ class AbstractPartEllipse : public CustomElementGraphicPart
 	private:
 		AbstractPartEllipse(const AbstractPartEllipse &);
 
+	signals:
+		void rectChanged();
+		void startAngleChanged();
+		void spanAngleChanged();
+
 		// methods
 	public:
 		virtual void startUserTransformation  (const QRectF &);