[ServiceWorker] Use “service worker” consistently (#818)

This patch also ensures that sentence case is used consistently for titles.

Note: this only affects the Markdown files.

Ref. https://github.com/slightlyoff/ServiceWorker/issues/705.
You can view, comment on, or merge this pull request online at:

  https://github.com/slightlyoff/ServiceWorker/pull/818

-- Commit Summary --

  * Use “service worker” consistently

-- File Changes --

    M README.md (32)
    M explainer.md (92)
    M implementation_considerations.md (120)

-- Patch Links --

https://github.com/slightlyoff/ServiceWorker/pull/818.patch
https://github.com/slightlyoff/ServiceWorker/pull/818.diff

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/pull/818