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.

ReserveDestination reservedest(&wallet, change_type);
    unsigned int outputs_to_subtract_fee_from = 0; 
    for (const auto& recipient : vecSend) {
        recipients_sum += recipient.nAmount;
        if (recipient.fSubtractFeeFromAmount) {
            outputs_to_subtract_fee_from++;
            coin_selection_params.m_subtract_fee_outputs = true;
        }
    }
    
    CScript scriptChange;
    bilingual_str error; 
    
    if (!std::get_if<CNoDestination>(&coin_control.destChange)) {
        scriptChange = GetScriptForDestination(coin_control.destChange);
    } else { 
        
        
        
        
        
        
        
        
        CTxDestination dest;
        auto op_dest = reservedest.GetReservedDestination(true);
        if (!op_dest) {
            error = _("Transaction needs a change address, but we can't generate it.") + Untranslated(" ") + util::ErrorString(op_dest);
        } else {
            dest = *op_dest;