[touch-events] Redirect "latest editors draft" link to github. (#18)

The [currently published spec](http://www.w3.org/TR/touch-events/) points to [https://dvcs.w3.org/hg/webevents/raw-file/v1/touchevents.html](https://dvcs.w3.org/hg/webevents/raw-file/v1/touchevents.html) as the latest editors draft.

As [for the pointer-events spec](https://lists.w3.org/Archives/Public/public-pointer-events/2015AprJun/0104.html), we should get GitHub redirection setup.

@AFBarstow can you take care of this?

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/touch-events/issues/18