Fixed broken links in Readme

[vernondegoede]

No description provided.

[googlebot]

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[vernondegoede]

Signed the CLA.

[googlebot]

CLAs look good, thanks!

[addyosmani]

Thanks for submitting a PR and the CLA. Taking a look now :)

[vernondegoede]

No problem at all! Thank you for all of your great work 👍