[touch-events] Switch default branch to gh-pages and delete master (#15)

Active work is now happening in the gh-pages branch, so the default branch should be switched and 'master' deleted to avoid confusion.  I don't appear to have the necessary permissions to do this.  @AFBarstow?

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/touch-events/issues/15