New demo version

Hello all, here's a new demo, with Unity's security patch as well as many new features - including a player position indicator, positive feedback for winning, a safety buffer at the top of the level to help avoid those pesky DNFs and more. We're particularly interested in feedback on the sound effects that play when objects collide with the player platform. 

Additionally, we recommend deleting older versions of our demo that do not have the security patch applied.

Thanks!