Update Notes 21st of July

[list] [*] Made the game slightly more difficult [*] Fixed glitch second mini-boss [*] Minor UI Updates [*] Added Manual Aim setting (for those who want) [*] Fixed a bug with zombie spawning (zombies would not respawn if the player ran around a lot) [*] Weapon and powerup balancing [*] SFX work [*] Minor bug fixes and improvements [*] XP Gems will now be despawned and aggregated if the player runs very far away from them [/list]