enhance kiosk/timetable

[1u]

#324

• can we add multiple locations as ?location=Openki&location=SQ131&location=SQ131Garden?
• grouping=loc or room or group (what if cours in in multiple groups?!?) think we leave this and allways do loc-grouping right? and sort room if some are indicated (how to mix this with not indicated ones?)
• highlighting: active=Denki

[sbalmer]

The current filtering infrastructure does not allow specifying alternatives. All predicates must match.

We could add a filter that allows multiple locations, like ?locations=Openki,SQ131,SQ131Garden. Another option would be to filter by coordinates so that you could say ?near=lat,lon[,radius].