fix for correct searching for irreversible block num
The code added here disapeared(by mistake) during merging #178 (closed) Lack of the code was responsible for crashing hivemind during restarting after SIG_INT in live sync
The code added here disapeared(by mistake) during merging #178 (closed) Lack of the code was responsible for crashing hivemind during restarting after SIG_INT in live sync