Use official @mailchimp/mailchimp_marketing library

- Switches to using the provided `@mailchimp/mailchimp_marketing` library
- The above required CoffeeScript 2.0 features, which aren't available
  with the current release of Hubot

.eslintrc.js

@@ -0,0 +1,15 @@
+module.exports = {
+  env: {
+    browser: true,
+    commonjs: true,
+    es2021: true,
+  },
+  extends: 'airbnb-base',
+  overrides: [
+  ],
+  parserOptions: {
+    ecmaVersion: 'latest',
+  },
+  rules: {
+  },
+};

index.js

@@ -0,0 +1,21 @@
+const fs = require('fs');
+const path = require('path');
+
+module.exports = function (robot, scripts) {
+  const scriptsPath = path.resolve(__dirname, 'src');
+  if (fs.existsSync(scriptsPath)) {
+    return (() => {
+      const result = [];
+      for (const script of Array.from(fs.readdirSync(scriptsPath).sort())) {
+        if ((scripts != null) && !Array.from(scripts).includes('*')) {
+          if (Array.from(scripts).includes(script)) { result.push(robot.loadFile(scriptsPath, script)); } else {
+            result.push(undefined);
+          }
+        } else {
+          result.push(robot.loadFile(scriptsPath, script));
+        }
+      }
+      return result;
+    })();
+  }
+};