CSPACE-5733: Moved vocabularyitems service to a new 'vocabulary' service type, thus...

CSPACE-5733: Moved vocabularyitems service to a new 'vocabulary' service type, thus pulling it out of the 'authority' type (and hence also out of the 'common' set of types, when authority services are optionally included in that set). Service types are currently used just in identifying document types to be scanned for authority references (refObjs) and in all records search, and in neither of these contexts should vocabularyitem records be included. We can either revert this change or include vocabularyitems in future sets as needed by future functionality.