GitLab

* Fix serviceworker output file and misc improvements

- Fix output file location for production build
- Cache more asset types: fonts and worker variants
- Parallelize a few tasks during initalization
- Only invalidate caches starting with our prefix
- Remove public/serviceworker.js before building
- Remove font preloads, they cause strange cors issues
- Misc eslint config adjustments

* remove webpack output files on watch-frontend