Correct the link of official website

[zhiwei-xu]

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[zhiwei-xu]

CLA signed.

[googlebot]

CLAs look good, thanks!

[trevj]

@zhiwei-xu Thanks for the fix!

[trevj]

This is a followup to:
#76

[trevj]

Weird, Travis never reported on this PR. Merging anyway since it clearly can't break the build.