[push-api] Expose options (#187)

This one builds on #182 to also address #183 and #184.

@kitcambridge, does this address your concerns?
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/push-api/pull/187

-- Commit Summary --

  * Voluntary server identification, imported version
  * Raw version
  * https links please
  * Exposing options on a subscription, making them immutable

-- File Changes --

    M index.html (115)

-- Patch Links --

https://github.com/w3c/push-api/pull/187.patch
https://github.com/w3c/push-api/pull/187.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/push-api/pull/187