[fetch] Clarify the hooks into RFC6265 (#221)

Fetch's current language around cookies is fairly vague. I think we can
do a little better, even without changing the Cookie specification.
You can view, comment on, or merge this pull request online at:

  https://github.com/whatwg/fetch/pull/221

-- Commit Summary --

  * Clarify the hooks into RFC6265

-- File Changes --

    M Overview.html (32)
    M Overview.src.html (32)

-- Patch Links --

https://github.com/whatwg/fetch/pull/221.patch
https://github.com/whatwg/fetch/pull/221.diff

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/pull/221