Update React Perf Example

[mrblueblue]

I've corrected the lastUpdate property from this.props.image from the incorrect key of lastUpdated

I've also corrected the use of the moment api. Since this.props.image.lastUpdate is epoch time, you have to invoke moment.unix() on it.

Lastly, I've updated React to version 0.14.2.

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[mrblueblue]

I signed it

[googlebot]

CLAs look good, thanks!

[jeffposnick]

CC: @paullewis

[paullewis]

Wondering if this sample needs to exist anymore. It's served it's purpose imo. @addyosmani @PaulKinlan wdyt?

[paullewis]

Sorry @mrblueblue, should've said thank you for the PR first. I'm just debating whether or not this really fits in the repo.

[addyosmani]

Did you want to move it elsewhere for future reference? If not, we could probably nix it.

[paullewis]

Just nix it; there's a copy on my GitHub fork (which is what's linked on the post)