fix #7036 making sure all spring beans are disposed when the vaadin session times out
ref #7550 replacing the selfregisration of the VaadinUserHelper to the vaadin session by a UserHelperAccess bean
ref #7550 moving the actual CdmUserHelper to cdmlib and making it available in cdm-vaadin by extending the UserHelper class and interface hierarchy
fix #7231 replacing SpringApplicationEventBus by scoped Vaadin4Spring Event Bus
flexible choosing of the viewDisplay per UI
fix #6997 toolbar with login logout and user name and icon