Update to 0.8.3 — Horde Slayer Steam update #1055215

This week focus was on perfomance, the game runs around two times faster on my machine and is more accessible to lower end hardware. Many stuttering issues on Windows have been fixed. A big change was the addition of the fog of war that hides the map and encourages player exploration. Changelog: - Perfomance Optimizations - 16 new rock sprites - Addition of fog of war, encouraging player exploration of the map - Improvements on player pixel art sprites - Changes to the world generation algorithm to remove some cases where there were areas on the map where the player coudn't reach.