EDIT

fixing #4406 (feature block image gallery broken)

disabling almost obsolte theme override palmweb_2_cdm_descriptionElement_Distribution()

hide empty bibliography

removing obsolete theme override palmweb_2_cdm_feature_nodes

introducing the api hook cdm_feature_node_blocks_alter and removing hook_cdm_feature_node_blocks_alter, this makes theme_cdm_feature_nodes obsolte, reducing speccial code in palmweb theme

more flexible table of content creation, hook_cdm_feature_node_toc_items_alter() no longer needed

hiding empty feature blocks

hiding all footnote keys in palmweb portal

fixing the feature block layout, footnotes and bibliography for palmweb, solving #4379 (Citations only consist of footnotes if bibliography block is enabled)

additional test