WICKET-4940 Make MountedMapper#getMatchedSegmentSizes(url) protected
WICKET-4939 AbstractAjaxTimerBehavior never triggers if attached to WebPage
Simplify some code by using a utility method.
Use consistently the getter methods for application and sessionId.
WICKET-4925 AbstractAjaxBehavior should clean stored reference to a component on unbind

Detach the Ajax behavior from its host component after component.remove(ajaxBehavior).
WICKET-4919 AjaxLazyLoadPanel needs a method to add components to the AjaxRequestTarget when the component is rendered
WICKET-4906 Form#visitFormComponents can cause ClassCastException