[push-api] Voluntary server identification, WebCrypto version (#180)

This uses WebCrypto constructs for describing the key.  I'm starting to think that we should just use a raw key (BufferSource) here and just cite X9.62.

@beverloo, any preferences?
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/push-api/pull/180

-- Commit Summary --

  * Voluntary server identification, imported version

-- File Changes --

    M index.html (50)

-- Patch Links --

https://github.com/w3c/push-api/pull/180.patch
https://github.com/w3c/push-api/pull/180.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/push-api/pull/180