libevent seems to have invaded `libbitcoin_common` via `url.cpp`

`url.cpp` is used only from `test/fuzz/string.cpp` and `wallet/rpcwallet.cpp`

libevent should only be required for bitcoind, bitcoin-cli and (due only to the hack of passing wallet names) bitcoin-qt

{"changePosition", RPCArg::Type::NUM,  "random", "The index of the change output"},
                            {"change_type", RPCArg::Type::STR,  "set by -changetype", "The output type to use. Only valid if changeAddress is not specified. Options are \"legacy\", \"p2sh-segwit\", and \"bech32\"."},
                            {"includeWatching", RPCArg::Type::BOOL,  "true for watch-only wallets, otherwise false", "Also select inputs which are watch only"},
                            {"lockUnspents", RPCArg::Type::BOOL,  "false", "Lock selected unspent outputs"},
                            {"feeRate", RPCArg::Type::AMOUNT,  "not set: makes wallet determine the fee", "Set a specific fee rate in " + CURRENCY_UNIT + "/kB"},
                            {"subtractFeeFromOutputs", RPCArg::Type::ARR,  "empty array", "The outputs to subtract the fee from.\n"
                            "                              The fee will be equally deducted from the amount of each specified output.\n"
                            "                              Those recipients will receive less bitcoins than you enter in their corresponding amount field.\n"
                            "                              If no outputs are specified here, the sender pays the fee.",
                                {
                                    {"vout_index", RPCArg::Type::NUM, RPCArg::Optional::OMITTED, "The zero-based output index, before a change output is added."},
                                },
                            },
                            {"replaceable", RPCArg::Type::BOOL,  "wallet default", "Marks this transaction as BIP125 replaceable.\n"
                            "                              Allows this transaction to be replaced by a transaction with higher fees"},
                            {"conf_target", RPCArg::Type::NUM,  "fall back to wallet's confirmation target (txconfirmtarget)", "Confirmation target (in blocks)"},
                            {"estimate_mode", RPCArg::Type::STR,  "UNSET", "The fee estimate mode, must be one of:\n"
                            "         \"UNSET\"\n"
                            "         \"ECONOMICAL\"\n"
                            "         \"CONSERVATIVE\""},
                        },
                        "options"},
                    {"bip32derivs", RPCArg::Type::BOOL,  "true", "Include BIP 32 derivation paths for public keys if we know them"},
                },
                RPCResult{
                    RPCResult::Type::OBJ, "", "",
                    {
                        {RPCResult::Type::STR, "psbt", "The resulting raw transaction (base64-encoded string)"},
                        {RPCResult::Type::STR_AMOUNT, "fee", "Fee in " + CURRENCY_UNIT + " the resulting transaction pays"},
                        {RPCResult::Type::NUM, "changepos", "The position of the added change output, or -1"},