[webcomponents] Link to CSS Scoping module spec? (#37)

Looking for "scope" or "/deep" or similar terms in the spec doesn't produce any meaningful result--because there is no mention to said selectors in this spec.

But as a developer I would expect at least a mention to: http://dev.w3.org/csswg/css-scoping/

This is the web, right? we link things together :globe_with_meridians: 

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/37