[touch-events] Move touchevents.html to index.html? (#26)

Since the default branch of this repo is now gh-pages, perhaps touchevents.html should be moved to index.html so that <https://w3c.github.io/touch-events/> is the "live" ED? 

WDYT? If there are no objections, I'll submit a PR.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/touch-events/issues/26