CbmBuildEventsQa: Treatment of noise was improved.
- Noise digis are now disregarded when matching a reconstructed event to a MC event. (only events which are pure noise are matched to -1)
- A histogram was added which shows the fraction of correctly matched digis of reconstructed events, which disregards noise digis during matching.
- A histogram was added which shows the fraction of noise digis of reconstructed events.