message: use the new epoch model to find out lastest epoch
diff: @@ -42,7 +42,14 @@ fn find_earliest_epoch(storage: &storage::Storage, minimum_epochid: blockchain::
  let mut epoch_id = start_epochid;
  loop {
  match tag::read_hash(storage, &tag::get_epoch_tag(epoch_id)) {
  - None => {},
  + None => {
  + match storage::epoch::epoch_read_pack(&storage.config, epoch_id).ok() {
  + None => {}
  + Some(h) => {
  + return Some((epoch_id, h));
  + }
  + }
  + },
  Some(h) => {
  println!("latest known epoch found is {}", epoch_id);
  return Some((epoch_id, h.into_bytes()))
  @@ -119,7 +126,7 @@ fn net_sync_faster(network: String, mut storage: Storage) {
  println!("Configured genesis-1 : {}", net_cfg.genesis_prev);
  // find the earliest epoch we know about starting from network_slotid
  - let (latest_known_epoch_id, mstart_hash, prev_hash) = match find_earliest_epoch(&storage, net_cfg.epoch_start, 40) {
  + let (latest_known_epoch_id, mstart_hash, prev_hash) = match find_earliest_epoch(&storage, net_cfg.epoch_start, 100) { // TODO
  None => { (net_cfg.epoch_start, Some(net_cfg.genesis.clone()), net_cfg.genesis_prev.clone()) },
  Some((found_epoch_id, packhash)) => { (found_epoch_id + 1, None, get_last_blockid(&storage.config, &packhash).unwrap()) }
  };
  