[push-api] A lower level version of #180 (#182)

I think that this is better than #180 on balance.  It's a little simpler.
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/push-api/pull/182

-- Commit Summary --

  * Voluntary server identification, imported version
  * Raw version

-- File Changes --

    M index.html (35)

-- Patch Links --

https://github.com/w3c/push-api/pull/182.patch
https://github.com/w3c/push-api/pull/182.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/push-api/pull/182