Final about page for 4.0. Enjoy the videos!

props ryelle, melchoyce, smashcut, wonderboymusic, helen.
fixes #29494.

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Pinking shears.

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About: Make sure the images are properly responsive.

props ocean90.
see #29494.

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WordPress 4.0.

Built from https://develop.svn.wordpress.org/trunk@29709


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