message: refactor unwraps to ? where possible
diff: @@ -645,7 +645,7 @@ impl ChainManager {
  // iterate through all validation passes
  for (idx, ops) in operations.iter().enumerate() {
  - let opb = OperationsForBlock::new(header.message_hash().unwrap(), idx as i8);
  + let opb = OperationsForBlock::new(header.message_hash()?, idx as i8);
  // create OperationsForBlocksMessage - the operations are stored in DB as a OperationsForBlocksMessage per validation pass per block
  // e.g one block -> 4 validation passes -> 4 OperationsForBlocksMessage to store for the block
  @@ -658,7 +658,7 @@ impl ChainManager {
  ctx.myself().tell(CheckChainCompleteness, None);
  // notify others that new all operations for block were received
  - let block = self.block_storage.get(&header.message_hash().unwrap())?.ok_or(StorageError::MissingKey)?;
  + let block = self.block_storage.get(&header.message_hash()?)?.ok_or(StorageError::MissingKey)?;
  self.shell_channel.tell(
  Publish {
  msg: AllBlockOperationsReceived {
  