splits the CalculateSkimMatrices.prepareAndCalculateNetworkMatrices() method such that there is a new variant, where a custom travel time object can be passed and
marks the eventsFilename arg as @Nullable such that is a bit more obvious, that it can be null and a FreeSpeedTravelTime is used in that case.
This change
CalculateSkimMatrices.prepareAndCalculateNetworkMatrices()method such that there is a new variant, where a custom travel time object can be passed andeventsFilenamearg as@Nullablesuch that is a bit more obvious, that it can be null and aFreeSpeedTravelTimeis used in that case.