Hotfix: add 2 harmless getters to TrackMatrix

include/core/processor/track_matrix.h

@@ -125,6 +125,9 @@ class TrackMatrix
 //        bool            markKeyframe(CaptureBasePtr _capture);
 //        bool            unmarkKeyframe(CaptureBasePtr _capture);
 
+        const map<SizeStd, Track>& getTracks(){return tracks_;}
+        const map<CaptureBasePtr, Snapshot >& getSnapshots(){return snapshots_;}
+
     private:
 
         static SizeStd track_id_count_;