While regtesting with [bitcoin-spock](https://github.com/msgilligan/bitcoin-spock) I noticed at some point the transaction creation via `sendtoaddress -> CreateTransaction()` fails, because the created transaction is larger than `MAX_STANDARD_TX_SIZE`.

During the process a lot of raw transactions are created, which have smallish outputs and when then using `sendtoaddress`, it appears to attempt to create a transaction that spends too many of those dust-ish outputs.

The transaction to create does not have many outputs, but it looks like it's caused by the coin selection, which selects too many inputs. Testing was done with a 0.9 branch, but on the first glimpse I believe this issue is as well be present in 0.10. If this is a known issue, and if there is already a guard against this behavior, I'd be happy about a hint.

Sorry in advance, I do not have a test script to reproduce this issue in an isolated manner. A potential fix would probably require to adjust the coin selection, so that it selects a combination of coins, which, in addition to the size of the rest of the transaction, is still smaller than the limit.

}
                
                if (IsDust(txout, wallet.chain().relayDustFee())) {
                    if (txout.nValue < 0) {
                        return util::Error{_("The transaction amount is too small to pay the fee")};
                    } else {
                        return util::Error{_("The transaction amount is too small to send after the fee has been deducted")};
                    }
                }
            }
            ++i;
        }
        nFeeRet = fee_needed;
    }
    
    if (scriptChange.empty() && nChangePosInOut != -1) {
        return util::Error{error};
    }
    if (sign && !wallet.SignTransaction(txNew)) {
        return util::Error{_("Signing transaction failed")};
    }
    
    CTransactionRef tx = MakeTransactionRef(std::move(txNew));
    
    if ((sign && GetTransactionWeight(*tx) > MAX_STANDARD_TX_WEIGHT) ||
        (!sign && tx_sizes.weight > MAX_STANDARD_TX_WEIGHT))
    {
        return util::Error{_("Transaction too large")};
    }
    if (nFeeRet > wallet.m_default_max_tx_fee) {