add some packages

node_modules/babel-traverse/README.md

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+# babel-traverse
+
+> babel-traverse maintains the overall tree state, and is responsible for replacing, removing, and adding nodes.
+
+## Install
+
+```sh
+$ npm install --save babel-traverse
+```
+
+## Usage
+
+We can use it alongside Babylon to traverse and update nodes:
+
+```js
+import * as babylon from "babylon";
+import traverse from "babel-traverse";
+
+const code = `function square(n) {
+  return n * n;
+}`;
+
+const ast = babylon.parse(code);
+
+traverse(ast, {
+  enter(path) {
+    if (path.isIdentifier({ name: "n" })) {
+      path.node.name = "x";
+    }
+  }
+});
+```
+[:book: **Read the full docs here**](https://github.com/thejameskyle/babel-handbook/blob/master/translations/en/plugin-handbook.md#babel-traverse)