Fix tryToFindNearbyPatients for patients using the drinks machine

When a patient in a queue is found and removed from the queue by
tryToFindNearbyPatients, the 'queue' actions is_in_queue flag
must be set to false. Otherwise, when the patient is using the
drinks machine at the moment of the rewrite, the after_use callback
of the drinks machine would create a new walk/use_bench or idle action
for the old queue.
Workaround for patients that fell of a queue

The workaround for patients, that fell of a queue, checks for patients
sitting on a bench while being queued, but are not found for 2 ticks
in the queue. It could happen sometimes, that in the moment before the
tick the patient was dequeued and doing the standing-up anim, which
requires the tick counter. When the patients problem is verfied he
is being sent to the reception.