improvments :

Added several difficulty slider on the options menu :

• Added a slider ranging to x0.75 to x2 the amount of health recovered upon pickup.

• Added a slider ranging to x0.75 to x2 the amount of armor recovered upon pickup.

• Added a slider ranging to x0.75 to x2 the amount of ammunitions found upon pickup.

• Added a slider ranging to x0.5 to x2 the amount of enemy health.

• Added a slider ranging to x0.5 to x2 the amount of enemy damage.

Added a 4th weapon slot. I'm still on the fence about this but maybe I'll make it an option on the difficulty screen.

Fixes :

Some ennemies now just stand and shoot the player on sight instead of rushing brainlessly.