ISIS-503: refactoring ObjectSpecificationDefault for actions and associations

- simplifying the overloading
- deprecated ObjectActionFilters, converted to ObjectAction.Filters
- deprecated ObjectAssociationFilters, converted to ObjectAssociation.Filters
ISIS-503: store contributee members along with regular members

- ie refactor how they are calculated

also:
- more refactorings of the overloads of getAssociations and getObjectActions
- rename "properties" to "metadataProperties" and convert to a field (in order to make available for sorting contributee actions later on when calculated and saved)
- rename "layoutProperties(...)" to "metadataProperties(...)"