### Describe the issue

Testing in bitcoin 0.13.0, calling `bitcoin-cli listsinceblock x` is outputting all double-spent transactions that are in the wallet, even those that were double-spent well and truly before x.
### Is the issue reproducible?

Yes
#### List steps to reproduce below:
1.   Create a double-spend send to your wallet (easiest using bip125)
2.   Wait until one confirms, and then wait a few more blocks
3.   Run `bitcoin-cli listsinceblock $(bitcoin-cli getbestblockhash)` and it will output the double spent transaction
### Expected behavior

The double-spent transaction that was conflicted before the block hash should be filtered

}
    return NullUniValue;
}
static CTransactionRef SendMoney(interfaces::Chain::Lock& locked_chain, CWallet * const pwallet, const CTxDestination &address, CAmount nValue, bool fSubtractFeeFromAmount, const CCoinControl& coin_control, mapValue_t mapValue)
{
    CAmount curBalance = pwallet->GetBalance(0, coin_control.m_avoid_address_reuse).m_mine_trusted;
    
    if (nValue <= 0)
        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid amount");
    if (nValue > curBalance)
        throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, "Insufficient funds");
    
    CScript scriptPubKey = GetScriptForDestination(address);
    
    CAmount nFeeRequired;
    std::string strError;
    std::vector<CRecipient> vecSend;
    int nChangePosRet = -1;
    CRecipient recipient = {scriptPubKey, nValue, fSubtractFeeFromAmount};
    vecSend.push_back(recipient);
    CTransactionRef tx;
    if (!pwallet->CreateTransaction(locked_chain, vecSend, tx, nFeeRequired, nChangePosRet, strError, coin_control)) {
        if (!fSubtractFeeFromAmount && nValue + nFeeRequired > curBalance)
            strError = strprintf("Error: This transaction requires a transaction fee of at least %s", FormatMoney(nFeeRequired));
        throw JSONRPCError(RPC_WALLET_ERROR, strError);
    }
    pwallet->CommitTransaction(tx, std::move(mapValue), {} );
    return tx;
}
static UniValue sendtoaddress(const JSONRPCRequest& request)