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 (auto ptr_wtx = wallet.GetWalletTx(outpoint.hash)) {
            
            if (ptr_wtx->tx->vout.size() <= outpoint.n) {
                return util::Error{strprintf(_("Invalid pre-selected input %s"), outpoint.ToString())};
            }
            txout = ptr_wtx->tx->vout.at(outpoint.n);
            input_bytes = CalculateMaximumSignedInputSize(txout, &wallet, &coin_control);
        } else {
            
            if (!coin_control.GetExternalOutput(outpoint, txout)) {
                return util::Error{strprintf(_("Not found pre-selected input %s"), outpoint.ToString())};
            }
        }
        if (input_bytes == -1) {
            input_bytes = CalculateMaximumSignedInputSize(txout, outpoint, &coin_control.m_external_provider, &coin_control);
        }
        
        if (coin_control.HasInputWeight(outpoint)) {
            input_bytes = GetVirtualTransactionSize(coin_control.GetInputWeight(outpoint), 0, 0);
        }
        if (input_bytes == -1) {
            return util::Error{strprintf(_("Not solvable pre-selected input %s"), outpoint.ToString())}; 
        }
        
        COutput output(outpoint, txout,  0, input_bytes,  true,  true,  true,  0,  false, coin_selection_params.m_effective_feerate);
        result.Insert(output, coin_selection_params.m_subtract_fee_outputs);
    }
    return result;
}
CoinsResult AvailableCoins(const CWallet& wallet,