API Add a getter for customisedObject property.

This is the only way to see if the ViewableData has been customised,
and is useful in situations when you want to further customise an
already-customised object.

view/ViewableData.php

@@ -208,6 +208,13 @@ class ViewableData extends Object implements IteratorAggregate {
 		);
 	}
 	
+	/**
+	 * @return ViewableData
+	 */
+	public function getCustomisedObj() {
+		return $this->customisedObject;
+	}
+
 	/**
 	 * @param ViewableData $object
 	 */