add some babel stuff

node_modules/@babel/helpers/README.md

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+# @babel/helpers
+
+> Collection of helper functions used by Babel transforms.
+
+## Install
+
+```sh
+npm install --save-dev @babel/helpers
+```
+
+## Usage
+
+Direct:
+
+```js
+import * as helpers from '@babel/helpers';
+import * as t from '@babel/types';
+
+const typeofHelper = helpers.get('typeof');
+
+t.isExpressionStatement(typeofHelper);
+// true
+```
+
+Inside a plugin:
+
+```js
+export default {
+  visitor: {
+    UnaryExpression(path) {
+      // The .addHelper function adds, if needed, the helper to the file
+      // and returns an expression which references the helper
+      const typeofHelper = this.addHelper("typeof");
+      t.isExpression(typeofHelper); // true
+  }
+};
+```
+
+## Defining Helpers
+
+> **NOTE**: This package is only meant to be used by the packages inluded in this repository. There is currently no way for third-party plugins to define an helper.
+
+Helpers are defined in the `src/helpers.js` file, and they must be valid modules which follow these guidelines:
+ - They must have a default export, which is their entry-point.
+ - They can import other helpers, exclusively by using default imports.
+ - They can't have named exports.
+
+```js
+helpers.customHelper = defineHelper(`
+  import dep from "dependency";
+  const foo = 2;
+  export default function getFooTimesDepPlusX(x) {
+    return foo * dep() + x;
+  }
+`);
+```