Added event selector to CbmReco and its YAML configuration

The digi event selector was integrated into CbmReco. It can be configured through the main YAML. The implementation is not yet general (contains number of stations in STS and TOF, and the number of BMON digis). The latter is relevant for the DC. I will do the proper generalization for all detectors later.

algo/evselector/DigiEventSelector.cxx

@@ -24,12 +24,19 @@ namespace cbm::algo
     //TO DO: Investigate possible algorithms that use bitset instead of std::unordered_map.
     //This requires consequtive addresses for modules and stations.
 
+    // --- Digi number in BMON
+    if (!(event.fData.fT0.fDigis.size() >= fParams.fMinNumDigisBmon)) return false;
+
+    // --- Number of STS stations
     if (0 < fParams.fStsMinStations) {
       if (!CheckSts(event.fData.fSts.fDigis)) return false;
     }
+
+    // --- Number of TOF layers
     if (0 < fParams.fTofMinLayers) {
       if (!CheckTof(event.fData.fTof.fDigis)) return false;
     }
+
     return true;
   }