PWA plugin #144

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Feature request

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What problem does this feature solve?

Add PWA (progressive web app) support

What does the proposed API look like?

plugins:
  - resolve: saber-plugin-pwa

How should this be implemented in your opinion?

• Use workbox in afterGenerate hook to generate public/service-worker.js
• Show a popup when update is ready

Are you willing to work on this yourself?

Yes but PR welcome.