Added CSS Animations
Added no-us class to index.html so if JavaScript isn't available, we'll have a class to pivot from
Progressively enhanced off of CSSAnimations

Using Toolkit's enhance-with and degrade-from mixins to provide alternatives.

Moved extension of %media-shared into cssanimation, as well as animation and overall border styling

In degrade from, zeroed out UL, made images extend %media-shared, attached border styling to each image.