message: Update comment on external block explorer service
diff: @@ -1357,7 +1357,7 @@ Wallet.prototype.accelerateTransaction = function accelerateTransaction(params,
  /**
  * Helper function to get a full copy (including witness data) of an arbitrary tx using only the tx id.
  *
  - * We have to use an external service for this (currently smartbit.com.au), since
  + * We have to use an external service for this (currently blockstream.info), since
  * the v1 indexer service (based on bitcoinj) does not have segwit support and
  * does not return any segwit related fields in the tx hex.
  *
  