EDITED 2019-02-08

`maxTxFee` is a global variable, used by both the raw transaction and wallet RPCs. It's set from `-maxtxfee`.

~listed in the global help text in init.cpp, but is only set in `WalletInit::ParameterInteraction()`. If the wallet is disabled, then `-maxtxfee` is ignored and the default is used.~

~This behaviour has existed since the mempool was changed to limit acceptance based on `maxTxFee` in https://github.com/bitcoin/bitcoin/commit/fa331db68bcc68e4c93fb45aaa30f911b0ecfe1a.~

~Short-term fix is to move the `-maxtxfee` handling to `InitParameterInteraction()` in init.cpp.~
EDIT: `maxTxFee` initiation bug fixed in #15357 

I don't think we should share this setting between the node and wallet.
#include <boost/algorithm/string/classification.hpp>
#include <boost/algorithm/string/replace.hpp>
#include <boost/algorithm/string/split.hpp>
#include <boost/thread.hpp>
#include <openssl/crypto.h>
#if ENABLE_ZMQ
#include <zmq/zmqabstractnotifier.h>
#include <zmq/zmqnotificationinterface.h>
#include <zmq/zmqrpc.h>
#endif
bool fFeeEstimatesInitialized = false;
static const bool DEFAULT_PROXYRANDOMIZE = true;
static const bool DEFAULT_REST_ENABLE = false;
static const bool DEFAULT_STOPAFTERBLOCKIMPORT = false;
static constexpr int DUMP_BANS_INTERVAL = 60 * 15;
std::unique_ptr<CConnman> g_connman;
std::unique_ptr<PeerLogicValidation> peerLogic;
std::unique_ptr<BanMan> g_banman;
#ifdef WIN32
#define MIN_CORE_FILEDESCRIPTORS 0
#else
#define MIN_CORE_FILEDESCRIPTORS 150
#endif
static const char* FEE_ESTIMATES_FILENAME="fee_estimates.dat";
/**
 * This is a minimally invasive approach to shutdown on LevelDB read errors from the
 * chainstate, while keeping user interface out of the common library, which is shared
 * between bitcoind, and bitcoin-qt and non-server tools.
*/
class CCoinsViewErrorCatcher final : public CCoinsViewBacked