Inconsistent interpretation of `fee` field in Deposited Event

[olga24912]

In current pipeline for transferring the Eth from Ethereum to Near, we initiate the transfer on Ethereum side by calling the depositToNear in EthCustodian contract (https://github.com/aurora-is-near/eth-connector/blob/master/eth-custodian/contracts/EthCustodian.sol#L86). After that the Deposited event is created. And this Deposited event contains the fee field.

According to:

• https://github.com/aurora-is-near/eth-connector/blob/master/eth-custodian/contracts/EthCustodian.sol#L85
• https://github.com/aurora-is-near/aurora-engine/blob/master/engine/src/connector.rs#L275

We would like to transfer the amount - fee to the new_owner and the fee to the relayer. But in current realization we transfer the amount to the new_owner and nothing to relayer: https://github.com/aurora-is-near/aurora-eth-connector/blob/master/eth-connector/src/lib.rs#L563

PR with this changes: #16

I propose to add comments in all contracts that it is deprecated field and extra check that fee == 0 into EthCustodian contract.

[mrLSD]

It's not exactly fully true, because we send that field in TransferMessage. End some other users, that can use custom Engine - can use it in their our mind.