Changed link to best practices talk to YouTube link

[svametcalf]

Because the google events page throws a 404, I have updated the docs with a direct link to the video on YouTube

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[svametcalf]

I signed it!

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CLAs look good, thanks!

[svametcalf]

I have added the link to the slides.

NOTE: Github was acting funny about a change that was made in the web editor, so I had to revert and revert the revert in order to force github to recognize the changes. These extra commits can be squashed without any issue.

[manolo]

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Reviewed 1 of 1 files at r3. Review status: all files reviewed at latest revision, 1 unresolved discussion.

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