NEW BUNKER DOOR CODE/KEYPAD SYSTEM

* Before when you entered a bunker you had to find a code and this was generated with each save. However, this causes issues, where codes wouldn't generate, etc.
* This new system implements 2 types of keycards the player can find.
* Standard Keycard: One time use on any bunker door
* All Access Keycard: Extremely rare and can be used multiple times on any bunker door
* Standard keycards will be spawned in briefcases placed around the map, these both have a random chance to spawn at their set locations and and a 75% chance to spawn that keycard.
* All Access Keycards are extremely rare, you could say some big dead person has it on them possibly, but again extremely rare.

CHANGES:

* Increased distance and volume of ice cream truck audio

BUG FIXES:

* Fix for map being blank