Vendor dependencies

Let's see how I like this workflow.

vendor/wasm-bindgen/examples/import_js/README.md

@@ -0,0 +1,15 @@
+# Importing non-browser JS
+
+[View documentation for this example online][dox] or [View compiled example
+online][compiled]
+
+[compiled]: https://rustwasm.github.io/wasm-bindgen/exbuild/import_js/
+[dox]: https://rustwasm.github.io/docs/wasm-bindgen/examples/import-js.html
+
+You can build the example locally with:
+
+```
+$ npm run serve
+```
+
+and then visiting http://localhost:8080 in a browser should run the example!