In previous implementation handler was not called more the one time after
Reset. It was caused by tick counter not being reset inside Reset method.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Call handler of the fractional block interval once between base interval
ticks by default. Add option to call handler of fractional block interval
multiple times (N times if fractional interval == BASE_INTERVAL / N).
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>