Revert "Merge branch 'XMLPropertiesNew'"

**Break a lot of thing.**

This reverts commit 1db1800572, reversing
changes made to 4c563821e8.

sources/editor/graphicspart/customelementpart.h

@@ -19,7 +19,6 @@
 #define CUSTOM_ELEMENT_PART_H
 
 #include "../../qet.h"
-#include "../../properties/propertiesinterface.h"
 
 class CustomElement;
 class ElementPrimitiveDecorator;
@@ -38,7 +37,7 @@ class QGraphicsSceneMouseEvent;
 	there is no point for those classes to store their visual representation
 	with anything more complex than a QImage.
 */
-class CustomElementPart: public PropertiesInterface {
+class CustomElementPart {
 	// constructors, destructor
 	public:
 	/**
@@ -62,6 +61,14 @@ class CustomElementPart: public PropertiesInterface {
 	
 	// methods
 	public:
+	/**
+		Load the primitive from an XML element that describes it
+	*/
+	virtual void fromXml(const QDomElement &) = 0;
+	/**
+		Export the primitive as an XML element
+	*/
+	virtual const QDomElement toXml(QDomDocument &) const = 0;
 	/**
 		Set a specific property of the primitive
 	*/
@@ -85,7 +92,7 @@ class CustomElementPart: public PropertiesInterface {
 		Make this part fit into the provided rectangle.
 	*/
 	virtual void handleUserTransformation(const QRectF &,
-						  const QRectF &) = 0;
+					      const QRectF &) = 0;
 	/// @return a pointer to the parent element editor
 	virtual QETElementEditor *elementEditor() const;
 	/**