According to the help text of createrawtransaction, the following args are accepted:
```
Arguments:
1. "inputs"                (string, required) A json array of json objects
2. "outputs"               (string, required) a json object with outputs
3. locktime                  (numeric, optional, default=0) Raw locktime. Non-0 value also locktime-activates inputs
```

however, this does not match the named args ( https://github.com/bitcoin/bitcoin/blob/8152d3fe57a991e9088d0b9d261d2b10936f45a9/src/rpc/client.cpp#L84 )

Imo, backporting a breaking change to 0.14.1 is reasonable. Though, I'd like to hear other opinions.
LOCK(cs_main);
    RPCTypeCheck(request.params, boost::assign::list_of(UniValue::VSTR)(UniValue::VBOOL));
    
    CMutableTransaction mtx;
    if (!DecodeHexTx(mtx, request.params[0].get_str()))
        throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "TX decode failed");
    CTransactionRef tx(MakeTransactionRef(std::move(mtx)));
    const uint256& hashTx = tx->GetHash();
    bool fLimitFree = true;
    CAmount nMaxRawTxFee = maxTxFee;
    if (request.params.size() > 1 && request.params[1].get_bool())
        nMaxRawTxFee = 0;
    CCoinsViewCache &view = *pcoinsTip;
    const CCoins* existingCoins = view.AccessCoins(hashTx);
    bool fHaveMempool = mempool.exists(hashTx);
    bool fHaveChain = existingCoins && existingCoins->nHeight < 1000000000;
    if (!fHaveMempool && !fHaveChain) {
        
        CValidationState state;
        bool fMissingInputs;
        if (!AcceptToMemoryPool(mempool, state, std::move(tx), fLimitFree, &fMissingInputs, NULL, false, nMaxRawTxFee)) {
            if (state.IsInvalid()) {
                throw JSONRPCError(RPC_TRANSACTION_REJECTED, strprintf("%i: %s", state.GetRejectCode(), state.GetRejectReason()));
            } else {
                if (fMissingInputs) {
                    throw JSONRPCError(RPC_TRANSACTION_ERROR, "Missing inputs");
                }
                throw JSONRPCError(RPC_TRANSACTION_ERROR, state.GetRejectReason());
            }
        }