### 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

if (it != pwallet->mapKeyMetadata.end()) {
            meta = &it->second;
        }
    }
    if (!meta) {
        auto it = pwallet->m_script_metadata.find(CScriptID(scriptPubKey));
        if (it != pwallet->m_script_metadata.end()) {
            meta = &it->second;
        }
    }
    if (meta) {
        ret.pushKV("timestamp", meta->nCreateTime);
        if (meta->has_key_origin) {
            ret.pushKV("hdkeypath", WriteHDKeypath(meta->key_origin.path));
            ret.pushKV("hdseedid", meta->hd_seed_id.GetHex());
            ret.pushKV("hdmasterfingerprint", HexStr(meta->key_origin.fingerprint, meta->key_origin.fingerprint + 4));
        }
    }
    
    
    
    UniValue labels(UniValue::VARR);
    std::map<CTxDestination, CAddressBookData>::iterator mi = pwallet->mapAddressBook.find(dest);
    if (mi != pwallet->mapAddressBook.end()) {
        labels.push_back(AddressBookDataToJSON(mi->second, true));
    }
    ret.pushKV("labels", std::move(labels));
    return ret;
}
static UniValue getaddressesbylabel(const JSONRPCRequest& request)