Description

Renamed to SlotCoordinator because is triggering events based on slot change.
Add SlotCoordinator class that should check for slot changes and if the current slot is the last slot in the epoch
executeEpochLottery in BabeService is invoked at the last slot of the current epoch -> when the isLastSlotInCurrentEpoch flag in the SlotChange event is true
Add methods for calculating the epoch start slot number for specified epoch index and also a method for calculating the last slot number of current epoch

TODO

Additional implementation should be added in BabeService that handles block creation on slot change