message: remove couple of unwrap by overwritting the binding with a ok_or(Error) pattern
diff: @@ -195,31 +195,23 @@ impl Ledger {
  }
  }
  - if block0_start_time.is_none() {
  - return Err(Error::Block0(Block0Error::InitialMessageNoDate));
  - }
  -
  - if discrimination.is_none() {
  - return Err(Error::Block0(Block0Error::InitialMessageNoDiscrimination));
  - }
  -
  - if slot_duration.is_none() {
  - return Err(Error::Block0(Block0Error::InitialMessageNoSlotDuration));
  - }
  + // here we make sure those specific parameters are present, otherwise we returns a given error
  + let block0_start_time =
  + block0_start_time.ok_or(Error::Block0(Block0Error::InitialMessageNoDate))?;
  + let discrimination =
  + discrimination.ok_or(Error::Block0(Block0Error::InitialMessageNoDiscrimination))?;
  + let slot_duration =
  + slot_duration.ok_or(Error::Block0(Block0Error::InitialMessageNoSlotDuration))?;
  let static_params = LedgerStaticParameters {
  block0_initial_hash,
  - block0_start_time: block0_start_time.unwrap(),
  - discrimination: discrimination.unwrap(),
  + block0_start_time: block0_start_time,
  + discrimination: discrimination,
  };
  - let system_time =
  - SystemTime::UNIX_EPOCH + Duration::from_secs(block0_start_time.unwrap().0);
  + let system_time = SystemTime::UNIX_EPOCH + Duration::from_secs(block0_start_time.0);
  let timeline = Timeline::new(system_time);
  - let tf = TimeFrame::new(
  - timeline,
  - SlotDuration::from_secs(slot_duration.unwrap() as u32),
  - );
  + let tf = TimeFrame::new(timeline, SlotDuration::from_secs(slot_duration as u32));
  let slot0 = tf.slot0();
  // TODO -- configurable slots per epoch
  