Ember Service Worker Versions Save

Drop enforcement of resolutions by pre-install script. This solution does not work for ember installations.

Security updates, documentation fixes, and dropped Node 8 support.

• Dropping support for node 6 ba601b3
• Clean up dependencies 305aa54
• Migrate fastboot test b70f976
• Test acceptance-test in multiple versions of Ember e1d751a
• Add service worker file name customization option 15183e1
• Update rollup output export options to 1.0+ syntax 4f97960

https://github.com/DockYard/ember-service-worker/compare/v0.7.2...vminor