[fetch] Explain some of the design decisions behind CORS (#206)

See https://lists.w3.org/Archives/Public/www-tag/2016Jan/0015.html by @sicking for the common things folks wonder about.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/issues/206

Received on Tuesday, 26 January 2016 22:29:13 UTC