change docs

docs/api/materials/Material.html

@@ -252,7 +252,12 @@
 		<div>
 		Defines whether this material is visible. Default is *true*.
 		</div>
-
+		
+		<h3>[property:object userData]</h3>
+		<div>
+		An object that can be used to store custom data about the Material. It should not hold
+		references to functions as these will not be cloned.
+		</div>
 
 		<h2>Methods</h2>