Preload all images to avoid accessing disk every frame.
Add short sleep to avoid busy-looping
Check current state to avoid re-compositing when nothing has changed
Addressing bug #11:
Updated keypress logic. The image now matches the most-recently-pressed key which is still pressed (For example: if you hold both keys, it stays on the most recent. if you hold one key and tap the other, it switches between the two, matching the taps)
Addressing performance concerns from issue #8:
Addressing bug #11: