[fetch] Add an example using Response body (#138)

Addressing #118.
You can view, comment on, or merge this pull request online at:

  https://github.com/whatwg/fetch/pull/138

-- Commit Summary --

  * Add an example using Response body

-- File Changes --

    M Overview.html (27)
    M Overview.src.html (25)

-- Patch Links --

https://github.com/whatwg/fetch/pull/138.patch
https://github.com/whatwg/fetch/pull/138.diff

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/pull/138