BookReader not loading higher-resolution images for high DPI screens by default

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I've noticed on archive.org that the book reader doesn't take advantage of high resolution screens (e.g. on Macs and iPhones) and the images therefore look a bit blurry unless you zoom in. I see that this was fixed a few years ago in #378 by using srcset, but it looks like the code was rewritten since then; there's still support for it, controlled by useSrcSet in src/BookReader/options.js where the default is useSrcSet: false, even though the comment above it says "On init, by default, we want to use srcSet for images." I tried changing that line to useSrcSet: true and it seems to work correctly that way. The default was changed from true to false in #651 and I don't see an explanation for why in the commit note. Was this intentional or could we change it back to true? I find it makes a big difference in legibility when reading books on small screens.