### 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

HelpExampleCli("getaddressesbylabel", "\"tabby\"")
            + HelpExampleRpc("getaddressesbylabel", "\"tabby\"")
                },
            }.Check(request);
    LOCK(pwallet->cs_wallet);
    std::string label = LabelFromValue(request.params[0]);
    
    UniValue ret(UniValue::VOBJ);
    std::set<std::string> addresses;
    for (const std::pair<const CTxDestination, CAddressBookData>& item : pwallet->mapAddressBook) {
        if (item.second.name == label) {
            std::string address = EncodeDestination(item.first);
            
            
            
            bool unique = addresses.emplace(address).second;
            assert(unique);
            
            
            
            
            ret.__pushKV(address, AddressBookDataToJSON(item.second, false));
        }
    }
    if (ret.empty()) {
        throw JSONRPCError(RPC_WALLET_INVALID_LABEL_NAME, std::string("No addresses with label " + label));
    }
    return ret;
}
static UniValue listlabels(const JSONRPCRequest& request)