Gallery Refactor

[sirugh]

I was going to create a talon for the Gallery component and I started doing a little refactoring. Turns out we can pretty much remove the GalleryItems component and we can simplify how Gallery works. In doing this I discovered that there's pretty much no talon to be written for Gallery.

It is important to note that Gallery is used in Category and in Search. In both cases there may be a different number of incoming or expected items being rendered which was counterintuitive when you looked at the hardcoded pageSize value.

So what I did was remove the pageSize prop and instead put the onus on the parent component. In this case, Category knows that it expects 6 items so it generates an empty placeholder array.

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[jimbo]

This is fine. Overall, I don't think there's a lot of value in eliminating GalleryItems, but it's good to strip out the hardcoded pageSize.

[sirugh]

I disagree -- GalleryItems wasn't doing anything important and I'd rather simplify the codebase than keep old things around just because.