Room closed in the middle of lab session

[hnrklssn]

It's quite confusing and irritating for everyone involved when a room times out and is removed, while a lab is active and people are queueing for help. I propose we never remove rooms when the following criteria hold:

• The room is not empty. Could be limited to just making sure the queues aren't empty.
• It's before 18 on a week day

[bjornregnell]

There is a check that the room is not active, see here: https://github.com/bjornregnell/sigrid/blob/master/src/main/scala/model.scala#L94