Usage:
const express = require("express");
const bodyParser = require("body-parser");
const Request = require("request")(process.env.API_KEY);
...
const paymentAddress = "0xYOUR_PAYMENT_ADDRESS";
const request = new Request(process.env.API_KEY, paymentAddress);
const app = express();
app.use(bodyParser.json());
app.post("/request", request.handler());
const listener = app.listen();