LPS-35335 replace always exportable portlets for the site data portlets
LPS-35335 remove the concept of always exportable portlets
LPS-35335 don't show the section associated to portlet configuration or content if there isn't any dataHandler
LPS-35335 apply same changes to publish_layouts
LPS-35335 remove isAlwaysStaged since we will now be based on content
LPS-35335 apply same changes to staging