Provide an API to get dynamic pages from java script.

When trying to connect the "entered" or "left" events for an userdefined page via gui.pageWidgetByObjectName("DynamicPage").entered.connect(dynamicPageEntered) I get the following error:

TypeError: Result of expression 'gui.pageWidgetByObjectName("DynamicPage").entered' [undefined] is not an object

I guess it is not implemented yet but should be consistent for static and dynamic pages.