v0.5.4 (mostly) mobile bug fixes

This week's release brings lots of aesthetic improvements and fixes:

• Menu selection particles are now a sweeping oval instead of the cloud (improves performance on most devices)
• Fixed some virtual stick draw position issues which occurred on screens bigger than 1920x1080
• Added a sound for bonking off of the screen boundaries
• Added a "heartbeat" sound that plays while time is stopped

This coming week will be some more mobile tweaks, as I ended up wanting to reconsider the input some more. Other than that, I might try to push for Steam, iOS, and Google Play releases all at once. Let me know what you think, and, as always, thanks for playing!