Add workaround for hello_world running in Chrome

Fixes #50.

examples/hello_world/index.js

@@ -3,6 +3,15 @@
 // will work here one day as well!
 const js = import("./hello_world");
 
-js.then(js => {
+Promise.all([
+  js,
+
+  // Due to https://github.com/webpack/webpack/issues/6475, Webpack does not
+  // support sync wasm imports larger than 4kB in Chrome. We use wasm2es6js to
+  // hack around this and need to defer our call until the converted wasm
+  // module is asynchronously loaded. Uncomment this line to enable.
+  // This hack is not necessary in Firefox.
+  // import("./hello_world_wasm.js").then(wasm => wasm.booted),
+]).then(([js]) => {
   js.greet("World!");
 });