Add the address of a created contract in the receipt?

[fjarri]

What feature should we add?

Currently when one applies a transaction that creates a contract, the address of the created contract is returned in a ComputationAPI object. It is not particularly convenient when one wants to emulate Ethereum RPC because when a transaction receipt is requested at a later time, that object is not possible to obtain anymore given the transaction hash. Would it be possible to include that information in ReceiptAPI instead, so that it could be obtained when calling get_receipts() on the block?