Show next-day events on agenda

[bjoernmartin]

Especially when looking for a room towards the end of the day, it might be interesting to see right away if the room is available the next day (or even next few days, maybe the rest of the week?).

At the moment I only see if there is a slot available for today, and if I want to see if it's available the next day I have to get back to a device that has access to that room's calendar. I'd like to avoid having to do that.