As an authenticated user, I can transact on the OMG Network (including syncing and confirming).

[T-Dnzt]

Ensure we are able to submit transactions to the OMG Network Childchain (or Watcher). We already have the notion of BlockchainTransaction that can be used to reference the transaction on our side and track the submission progress.

Make also sure that the blockchain transactions can be retrieved by calling /blockchain_transactions.all.