also add null check in comparator of nomenclaturalReferenceSelectionDialog
ref #5837: if nomenclatural titleCache and titleCache are equal only one is shown in selection dialog
ref 6061: using * at the beginning of search pattern triggers a search on abbrevTitleCache and titleCache
fix #5837: fix the filter of the selection dialog of nomenclatural reference and author
ref #5828 abbrevTitle and titlecache are displayed in nomenclatural selectionDialogs
ref #5837 add new NomenclaturalReferenceSelectionDialog