Make camera configurable

[lethal-guitar]

Make it possible to configure the camera dead zones. There would be a couple of options:

• Original - original camera without changes
• Centered - always keep Duke in the center of the screen, so the camera scrolls sooner
• Edges - always keep Duke at the opposite edge of the screen. If he is moving to the right, keep him at the left edge of the screen, when moving to the left, keep him at the right edge.