Fix digi counting in event header
Before this fix only the number of digis of the last component of a subsystem endet up in the counter of the event header. Now an Add function is used and the counters a resetted at the beginning of each timeslice.
Before this fix only the number of digis of the last component of a subsystem endet up in the counter of the event header. Now an Add function is used and the counters a resetted at the beginning of each timeslice.