Widget: Update demo to work with 1.6

Author: jzaefferer

demos/widget/default.html

@@ -50,7 +50,7 @@
 
 				this.changer = $( "<button>", {
 					text: "change",
-					className: "custom-colorize-changer"
+					"class": "custom-colorize-changer"
 				})
 				.appendTo( this.element )
 				.button();