housekeeping

[leesio]

I noticed a couple of things while working on the library

• Update example
  • Use the current API
  • Import the built service worker, rather than the unbuilt source
  • Start the client in an event handler - Some browsers only allow requesting permission to send notifications in response to a user gesture
• Bump package-lock.json - it seems like this wasn't updated when release 1.1.0 was prepared