feature: expose GalleryItem

[marlonmarcello]

Goal

Right now there is no way to target the <li> item that is auto generated and wrapped around the render function. So trying to customize it while using CSS modules require the use of the :global mixin.

The goal of this PR is to expose the <GalleryItem /> component to allow for further customization of the automatically rendered <li> tag.

This is a breaking change so I bumped the version to 2.0.0.

Usage

Not much changes, only things is that now users need to return a <GalleryItem /> component inside their render function:

<Gallery items={GALLERY_ITEMS}>
    <GalleryMain
      renderGalleryItem={({ item, i, active }) => (
        <GalleryItem key={i} index={i} active={active}>
          <img src={item.image} alt={item.alt} />
        </GalleryItem>
      )}
    />
</Gallery>

[liamegan]

LGTM

[andrewrubin]

This works for me! Thanks for the update. Do you mind updating the docs as well? No rush.

If this is not urgent, I think we should prep a release before merging this to main, which also includes a fix to #3.