select for category conjunction added
localization for category conjuction added
hidden field for category conjunction added
property categoryConjunction added
building AND queries from categories (venues, event types, genres) implemented
work in progress: reading category conjunction and setting up demand accordingly implemented

There is still an issue when venues, genres or event types are set in list plugin _and_ in overwrite demand (i.e. from QuickMenu): all categories from both list lugin and overwrite demand are conjunct by AND. This may lead to unexpected behavior in frontend!