docs(tutorial/12 - Applying Animations): describe your change...

[spoonraker]

Grammar improved for clarity

[googlebot]

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[spoonraker]

I signed it!

[googlebot]

CLAs look good, thanks!

[matsko]

Landed as 00bf218 and 99fc6cd for 1.5 and 1.4. Thanks for making these fixes :)

[matsko]

Excellent work!