A better progress indicator for image galleries

We've added a better way to discover images in a gallery. Before it could be hard to tell that there was more than one image, because we only showed it via a small number in the top left corner. Well, now we've shrunken down the main image so you can see just a little bit of the next image hinting there's more images in the slideshow. We hope this will improve the overall user experience of slideshows.