Manage Internal Transactions

[villanuevawill]

Currently, we run into a few issues:

1. Our current architecture does not pass enough information on events. As a result, we have to pull the transaction to find the original inputs: https://github.com/Bounties-Network/BountiesAPI/blob/master/contract_subscriber/eventsRetriever.js#L37-L42 . This approach will not work with wrappers around the std bounties contract. This is because a wrapper contract will create an internal transaction that is not reliable enough to track the original inputs.
2. Leaderboard and other endpoints track the fulfillment address from msg.sender. This means in the case of an internal transaction, we must grab this value from the data schema. This is a bit tricky and will definitely require us to branch out the code.