Fix the joyticks

[SiegeLord]

Joysticks have been subtly and not so subtly broken for years. If we want to have a joystick feature at all, it should work well.

SDL has established a standard for joystick interpretation, and other libraries have sought to emulate it. It makes sense to do the same. If the SDL API appears to be deficient, at least our API should be a strict improvement over it.

Tasks:

• Investigate the SDL/GLFW APIs for joysticks, see if it makes sense to map to Allegro's.
• Adjust the code for all 3 major platforms to start. Use the joystick_version compatibility switch to maintain compatibility with the older code.

[ReiquelApplegate]

https://www.libsdl.org/release/SDL-1.2.15/docs/html/joystick.html