Improve web store listing with more images

[voltrevo]

We should add more images to our web store page:

Let's put together the following:

• At least one more screenshot
• Small promo tile
• Large promo tile
• Marquee promo tile

And then

• Publish it

Google provides some more details about these:

Small promo tile: 440x280 pixels   Appears on the homepage, category pages, and in search results.

Large promo tile: 920x680 pixels   Not currently used. You do not need to provide a large promo tile at this time.

Marquee image: 1400x560 pixels   This image is used if your item is chosen for the marquee feature (the rotating carousel on the top of the Chrome Web Store homepage). To increase your chances of being featured, ensure your marquee image is uncluttered, high-resolution, and has consistent branding elements to your other assets so users can immediately associate it with your extension and brand.