[manifest] define URL Scope (closes #114) (#291)

* First go at defining this based on extensive discussions over the last year. 
You can merge this Pull Request by running:

  git pull https://github.com/w3c/manifest url_scope

Or you can view, comment on it, or merge it online at:

  https://github.com/w3c/manifest/pull/291

-- Commit Summary --

  * define URL Scope (closes #114)

-- File Changes --

    M index.html (121)

-- Patch Links --

https://github.com/w3c/manifest/pull/291.patch
https://github.com/w3c/manifest/pull/291.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/manifest/pull/291