message: document how to run the e2e tests locally
diff: @@ -168,3 +168,8 @@ Ensure you've followed the above development instructions and then:
  ```bash
  yarn test
  ```
  +
  +## End-to-End tests
  +
  +Make sure you've got your riot development server running (by doing `yarn start` in riot-web), and then in this project, run `yarn run e2etests`.
  +See `test/end-to-end-tests/README.md` for more information.
  