Add meta tag for google webmaster tools
Merge pull request #185 from github/webmaster-tools-meta-tag

Add meta tag for google webmaster tools
Remove sitemap.xsl
Merge pull request #186 from github/how-about-laughing-octo-hipsters

Remove sitemap.xsl
Remove google verification header

I don't think we need this now that we've verified the site.
Merge pull request #188 from github/i-want-freezing-lanas

Remove google verification header
Update ZeroClipboard to v1.3.1.