Built against `master` branch 801dd40666d1e6009920ad3ff755c7bb993b2a62:

If I have no wallet.dat file and run:

    bitcoind -usehd=0

A new wallet.dat file is created and an HD seed is assigned.

I see an error message in the source:

    "Error loading %s: You can't disable HD on an already existing HD wallet or create new non-HD wallets."

but that doesn't get shown because `fFirstRun` is true, and so the code which checks for `-usehd` values doesn't run.

If it's no longer possible to create non-HD wallets, specifying -usehd=0 when creating a wallet should be an error, and not get silently ignored.
{
    CWalletDB walletdb(*dbw);
    if (!walletdb.TxnBegin())
        return false;
    int64_t nNow = GetAdjustedTime();
    
    CAccountingEntry debit;
    debit.nOrderPos = IncOrderPosNext(&walletdb);
    debit.strAccount = strFrom;
    debit.nCreditDebit = -nAmount;
    debit.nTime = nNow;
    debit.strOtherAccount = strTo;
    debit.strComment = strComment;
    AddAccountingEntry(debit, &walletdb);
    
    CAccountingEntry credit;
    credit.nOrderPos = IncOrderPosNext(&walletdb);
    credit.strAccount = strTo;
    credit.nCreditDebit = nAmount;
    credit.nTime = nNow;
    credit.strOtherAccount = strFrom;
    credit.strComment = strComment;
    AddAccountingEntry(credit, &walletdb);
    if (!walletdb.TxnCommit())
        return false;
    return true;
}
bool CWallet::GetAccountPubkey(CPubKey &pubKey, std::string strAccount, bool bForceNew)