message: Document issue with file watchers
  Closes
diff: @@ -20,6 +20,9 @@ yarn
  yarn start
  ----
  +[NOTE]
  +On some platforms, `yarn start` may fail with an error like `Error: ENOSPC: System limit for number of file watchers reached`. To fix this, you need to increase the limit of file watchers on your system. The command may vary depending on the platform, please refer to link:https://github.com/guard/listen/wiki/Increasing-the-amount-of-inotify-watchers[these instructions].
  +
  A new browser window should automatically open.
  But, if it doesn't then use:
  `http://localhost:3000`
  