[fetch] Add "Streams" section. (#119)

Add "Streams" section in part of adding the body property to Response. Addressing #118.
You can view, comment on, or merge this pull request online at:

  https://github.com/whatwg/fetch/pull/119

-- Commit Summary --

  * Add "Streams" section.

-- File Changes --

    M Overview.html (102)
    M Overview.src.html (86)

-- Patch Links --

https://github.com/whatwg/fetch/pull/119.patch
https://github.com/whatwg/fetch/pull/119.diff

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/pull/119