Work on README and do some polishing

This was mostly working on my README, which wasn’t too difficult, but I had to figure out how I wanted to embed my images. I ended up just linking to the ones that I uploaded to Itch.io, because they were hosting them for me. I followed the README guidelines from Stardance, and I think I have a solid, professional README.

Once the README was written, I reused most of the text for my Itch.io page and made that look presentable. I also fixed some issues with window scaling, but these changes were minor.

Really all I have left at this point is to make some levels, which I’ve clearly been putting off. As of writing this, I have about two days left in the game jam, so I feel comfortable with my time.