REF #788: clear jem_categories.ordering, top category not required on Categories view
REF #782, #787, #791: legend on categorycal, view params, archive, ...

- JEM version set to 1.9.8 (xml)
- show (reduced) legend on category calendar with event count
- fix params of category (list) view
- show event count on subcategories (also used for Show empty subcategories)
- regard "task=archive" on subcategory links (Category/ies views)
- harmonize view params to get more consisent look (menu items)
- on Venue calendar move id from params to link (uri) conform to all other views
- add back colorpic on Week calendar
- internal: startdayonly now means "start day only" and not "all days" - reduces developer's confusion