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.

nFeeRet = result->GetSelectedValue() - recipients_sum - change_amount;
    
    
    if (!coin_selection_params.m_subtract_fee_outputs && fee_needed > nFeeRet) {
        return util::Error{Untranslated(STR_INTERNAL_BUG("Fee needed > fee paid"))};
    }
    
    if (nChangePosInOut != -1 && fee_needed < nFeeRet) {
        auto& change = txNew.vout.at(nChangePosInOut);
        change.nValue += nFeeRet - fee_needed;
        nFeeRet = fee_needed;
    }
    
    if (coin_selection_params.m_subtract_fee_outputs) {
        CAmount to_reduce = fee_needed - nFeeRet;
        int i = 0;
        bool fFirst = true;
        for (const auto& recipient : vecSend)
        {
            if (i == nChangePosInOut) {
                ++i;
            }
            CTxOut& txout = txNew.vout[i];
            if (recipient.fSubtractFeeFromAmount)
            {
                txout.nValue -= to_reduce / outputs_to_subtract_fee_from; 
                if (fFirst) 
                {
                    fFirst = false;
                    txout.nValue -= to_reduce % outputs_to_subtract_fee_from;