Final touches on the README, itch.io page, player movement, and sound effects

I finished the GitHub readme file and added a short gameplay gif to attract the reader’s attention. I drew a stylized button link to make the “Try It” link pop.
I made a background image for the itch.io page and wrote a description.
I added some game juice by adding coyote time, which allows the player to jump even after they’ve fallen a little bit off a ledge. I also added squash and stretch to make the game feel more bouncy.
Finally, I made some 8-bit sound effects using JSFXR. They’re really simple as of now, but I think they’re enough for the kind of game I’m going for.
This will probably be the last devlog before I ship!