README: Add instructions for a world with async/await

README.md

@@ -176,6 +176,20 @@ also add `return wait();` to the end of your acceptance tests.
 While this currently still works without the `return`, it will fail once
 this library is updated to Mocha 3.x!
 
+In case your project supports the `async/await` feature of ES2016 you can
+simplify the test function to this:
+
+```js
+it('can visit /', async function() {
+  await visit('/');
+  expect(currentURL()).to.equal('/');
+});
+```
+
+- add the `async` keyword in front of the test `function`
+- add `await` in front of all async test helper calls
+- remove the `andThen()` wrappers
+
 
 Upgrading
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